Friday

July 31, 2015

July 31, 2015

Number of results: 46,332

**Algebra Grade 7 (Rotation)**

If you rotate a clock clockwise 90° from 3:00, what will it be?
*November 29, 2012 by rawr... im a dinosaur.... rawr*

**PreCalculus**

Problem: Identify the conic from the equation 13x^2-6(sq.rt.6)xy+7y^2-16=0 I have to choose from the following four answers: hyperbola (angle of rotation 45) hyperbla (angle of rotation 60) ellipse (angle of rotation 90) ellipse (angle of rotation 30) I used the discriminant...
*March 30, 2009 by Joanie*

**math**

what is the difference between translation , rotation, relections, and dilation in 8 grade work In 8th grade talk, I recommend you check the examples in your book. OR, if you put your definitions here, I can critique them.
*January 28, 2007 by jose*

**algebra**

1. Are the rotations of figures always congruent? Why are or why not? 2. A car tire rotates when you drive. How is this type of rotation different from a rotation in Geometry? What other type of transformation is happening to the car tire? Explain.
*September 6, 2013 by Unknown*

**7th grade math**

what is angle of rotation?
*January 6, 2010 by Jacqulynn *

**Chemistry**

If the specific rotation of Compound X is (-) 123.8º, what would be the observed rotation of its enantiomer, Compound Y, assuming the concentration and cell path length is the same? b. If a racemic mixture of Compound X and Compound Y were analyzed, what would be the observed ...
*March 31, 2011 by Nicole*

**Another astronomy (algebra-based physics) question**

I’d prefer thorough solutions, but if you can only provide formulas that would solve each part of the problem, that’d be helpful too :-) Thanks! Spinning too fast The rate of rotation of astrophysical objects that are held together by gravity (e.g., stars or planets) cannot be...
*March 4, 2009 by Mark*

**Math**

Can anyone please rephrase this. I really can't understand this term. Rotation symmetry: When a shape or design can be turned about its center of rotation, so it fits onto its outline MORE than once in a complete turn(360 degrees) I don't understand this. I don't get what ...
*February 4, 2010 by Sara*

**Chemistry(Please help)**

I know that to calculate the specific rotation for a compound you do observed rotation / path length(dm) * conc. (g/ml). I am confused about how to calculate the specific optical rotation for a compound. Thank you for your help!
*October 28, 2012 by Hannah*

**Fourth Grade Geometry**

Could someone tell me what the definitions of translation, reflection and rotation mean?
*January 9, 2008 by Tremaine*

**Organic Chemistry**

A 0.160 M solution of an enantiomerically pure chiral compound D has an observed rotation of 0.20° in a 1-dm sample container. The molar mass of the compound is 128.0 g/mol. (a) What is the specific rotation of D? (b) What is the observed rotation if this solution is mixed ...
*September 29, 2014 by Trish*

**Math **

[R] = [4/5 -3/5] and [S] = [-3/5 4/5] [-3/5 -4/5] and [4/5 3/5] are reflection matrices. Calculate [R·S] and verify that it can be identified as the matrix of rotation. Determine the angle of the rotation.
*October 17, 2014 by Wes*

**math**

What is the rule for finding coordinates after a 90 degree rotation? after a 180 degree rotation? after a 270 degree rotation?
*November 16, 2011 by Kory*

**grade nine space**

What is the difference between the terms rotation and revolution? I need to use the Earth to support my answer.
*January 17, 2011 by peyton*

**chemistry**

Calculate the specific rotation for Compound A, whose observed rotation was (+) 45.0 for a solution made from 0.400 g dissolved in 5 mL of chloroform solvent. The cell path length was 10 cm.
*February 18, 2015 by khushboo khan*

**MATH**

Figures that correspond under a translation, rotation, or reflection are said to be translation congruent, rotation congruent, or reflection congruent. Position two congruent figures on a piece of paper to satisfy each combination of congruences listed. Use tracing paper, ...
*August 28, 2009 by Anonymous*

**Pre algebra**

Kayla has a 41% grade average. On an exam that is worth 20% of her grade she gets a 100%. What is her grade now?
*May 25, 2011 by Ashley*

**geometry**

Figures that correspond under a translation, rotation, or reflection are said to be translation congruent, rotation congruent, or reflection congruent. Position two congruent figures on a piece of paper to satisfy each combination of congruences listed. Use tracing paper, ...
*October 24, 2009 by jeng*

**Chemistry**

Organic chemistry: an attempt at synthesizing a certain optically active compound resulted in a mixture of its enantiomers. The mixture had an observed specific rotation of 11.0 degrees. If it is known that the specific rotation of the R enantiomer is -33.6 degrees, determine ...
*November 4, 2010 by Tokey*

**Computer Science**

How do you create a rotation matrix that will represent a rotation of angle theta about a vector (x,y,z)? This is instead of rotating about an axis.
*February 16, 2008 by Mike*

**physics**

the rotation of earth is a period of 86164 seconds. the earth has a radius of 6380 km. how fast would you be moving due to earths rotation at the equator? also how fast would you be moving at a latitude of 27 degrees north of the equator? also calculate the centripetal ...
*February 24, 2014 by jake*

**physics**

pulsar is a rapidly rotating neutron star that emits radio pulses with precise synchronization, there being one such pulse for each rotation of the star. The period of rotation is found by measuring the time between pulses. At present, the pulsar in the central region of the ...
*March 17, 2008 by shelby*

**analytic geometry**

how to convert the small rotation of axes into capital rotation of axes?
*October 3, 2012 by shah*

**cCongruence and transformations?**

m (x,y) --> (-x,y) is what transformation reflection rotation or translation m (x,y) --> (y, -x) is what transformation reflection rotation or translation m (x,y) --> (2x,2y) is what transformation reflection rotation or translation how do you do this what are some ...
*August 27, 2013 by loli*

**6th grade science**

which soil conservation technique did George Washington Carver urge farmers to use??? 1) crop rotation 2) cover crops 3) contour plowing 4) no-till farming
*November 11, 2011 by Kate*

**7th grade science help the solar system Ms. Sue**

1. Most likely, ____ were formed when lava from the moon's interior flooded bowl-like regions on the moon's surface. (1 point) maria highlands craters basins 2. Depressions on the moon formed by large meteorites are called ____. (1 point) maria mountains craters highlands 3. ...
*October 17, 2012 by Delilah*

**Physics**

Which produces the largest torque? 30.0 N perpendicular to the center of rotation at a radius of 1.5 m 30.0 N perpendicular to the center of rotation at a radius of 0.25 m 60.0 N perpendicular to the center of rotation at a radius of 1.0 m 60.0 N perpendicular to the center of...
*January 15, 2014 by Gabe*

**Geometry - Angle of rotation**

What is the measure of the angle of rotation with respect to two lines that intersect to form a 25° angle? 25 degrees is how much one line is rotated from the other
*August 2, 2007 by John*

**Geometry**

1.1.Determine whether the regular pentagon has reflection symmetry, rotation symmetry, both, or neither. If it has reflection symmetry, state the number of axes of symmetry. If it has rotation symmetry, state the angle of rotation. For each type of symmetry, explain how you ...
*October 17, 2014 by D*

**Chemistry**

Suppose a student is measuring the optical rotation of a 1 M sample of (S)-(-)- Limonene. The path length is 13cm. What optical rotation should the student expect to measure?
*November 14, 2010 by Sunny*

**Chemistry **

The structure of Crestor (rosuvastatin), a medication used to reduce cholesterol, is shown below. If the specific rotation for this compound is known to be +100, what would be the specific rotation for the stereoisomer shown at the right?
*October 21, 2014 by Anonymous*

**Chem Help Please!**

A material has an optical purity of 50%. How much of each of the enantiomers is present. The R enantiomer of a material has rotation of +35. what is the rotation of the S enantiomers.
*October 8, 2014 by Josh*

**Chemistry **

What is the percentage of the S enantiomer in a sample of carvone that has a specific rotation of 30, given that the specific rotation of (R)-carvone is -61? How do i set up the problem?
*October 21, 2014 by Anonymous*

**ochem lab**

What is the expected observed rotation of a 9.1 x 10-5 M solution of compound X? Note: compound X has a specific rotation of [α]D20 = -49o and a molecular weight of 235.2 g/mol. In addition, the path length of the cell used to take the polarimetry measurement was 5.0 cm.
*April 2, 2012 by cn*

**Math 10**

A trundle wheel can be used to measure the walking distance between two locations. a) If the diameter of a trundle wheel is 45 cm, how far will a person have walked when the wheel makes one full rotation? b) If a person walks for 0.7 km, how many times has the wheel rotated? ...
*July 17, 2014 by Bree*

**math**

After a triangle is rotated 180 degrees, its vertices are at (-4,1),(-1,4), and (-5,-8). What were the coordinates of the vertices before the rotation? I think the answer is (1,-4), (4,-1),(8,-5). In rotation, the coordinates get switched. All I just did was switch the numbers...
*December 1, 2007 by robert*

**physics**

In an amusement park ride, cars are suspended from L = 4.22 m cables attached to rotating arms at a distance of D = 6.25 m from the axis of rotation. The cables swing out at an angle of θ = 49° when the ride is operating. What is the angular speed of rotation?
*February 18, 2012 by Jon Tuck*

**differential calculus**

a SECURITY CAMERA is centered 50 feet above a 100-foot hallway. it is easiest to design the camera with a constant angular rate of rotation, but this results in a variable rate at which the images of the surveillance area are recorded. so, it is desirable to design a system ...
*September 16, 2014 by =)*

**Cosmology**

Which of the following statements is not true of spiral arms: they tend to trail the rotation of the galaxy they are sites of star formation they are amplified by resonances between the epicyclic frequencies of stars and the angular frequency of the spiral pattern they arise ...
*March 1, 2013 by C*

**Math - Algebra**

Von's arcade uses 3 different colored tokens for its game machines. For 500, you can purchase any of the following combinations of tokens: 8 gold, 18 silver, and 7 bronze tokens; 8 gold, 14 silver, and 13 bronze tokens; or 16 gold, 6 silver, and 9 bronze tokens. What is the ...
*January 4, 2014 by Ashley Kate*

**Physics (please help!!)**

The Crab pulsar (m=2.00x10^30 kg) is a neutron star located in the Crab Nebula. The rotation rate of the Crab pulsar is currently about 30.0 rotations per second, or 60.0pi rad/s. The rotation rate of the pulsar, however, is decreasing; each year, the rotation period increases...
*April 15, 2011 by Abigail*

**Physics**

In an amusement park rocket ride, cars are suspended from L = 4.28-m cables attached to rotating arms at a distance of d = 6.10 m from the axis of rotation. The cables swing out at an angle of θ = 52.0° when the ride is operating. What is the angular speed of rotation?
*December 9, 2008 by Sandhya*

**Linear Momentum in Rotational motion**

It is known that for a mass (m) that moves with velocity (v) the linear momentum is (m)x(v). Now, assume we have a rod of mass (m) and radius (R) that rotates with constant angular velocity (w). Also, isolate only half of the cycle (rotation for 180 degrees). What is the ...
*February 11, 2007 by Nikos*

**Physics**

A rotating space station has radius 1270 m, measured from the center of rotation to the outer deck where the crew lives. What should the period of rotation be if the crew is to feel that they weigh one-half their Earth weight? I got 101.1 seconds... is this correct? Please help!
*June 3, 2012 by Brandi*

**Chemistry**

A pure sample of (R)-limonene has a specific rotation of +125.6. If a sample had a specific rotation of +35.6, how much of each enantiomer is present in the sample? Show your work. I dont even know where to begin....please help :(
*November 8, 2011 by Adrianna*

**Algebra(2 of 3)**

The vertices of ABC are A(-3,-4),B(-1,3),C(3,-2). The triangle is rotated 90 degrees counterclockwise. Use the rotation matrix [0 -1][1 0] to find the coordinates of C' A)(-3,2) B)(4,-3) C)(-3,-1) D)(2,3) I chose A [0 -1] x [-3 -1 3][-4 3 -2] =
*February 18, 2008 by Jon*

**pre algebra**

my grade is 83.17 in pre algebra in college, but the final exam is worth 300 points. If I got a B or B- or a C on the final, what would my grade be overall?
*March 10, 2011 by Amber shall*

**Science 6th grade Earth's day and night ANSWERS**

1. how does earth's rotation cause day and night? (1pt) As the earth rotates toward the east the sun appears to rise in the east and set in the west. 2.Roughly how many times does the earth rotate during each complete revolution? (1pt) 365. 3. Saturn's day is roughly 10 hours ...
*March 12, 2014 by Queen elsa*

**8th grade math**

please help one blade of a fan is parallel to the floor. what degree of rotation of the fan puts the blade at the top of the fan
*May 21, 2012 by codey*

**College Algebra**

solve the polynomial inequality and graph on number line. express in set interval rotation. Show work x^3 - 3x^2 - 9x + 27 < 0
*November 24, 2013 by Jenn*

**math**

Mr. Doodle’s grade distribution over the past 3 years for a course in college algebra is shown in the chart below. Grade Number A 45 B 180 C 210 D 95 F 65 I 5 If Jane plans to take a college algebra course with Mr. Doodle, determine the empirical probability that she receives ...
*May 29, 2011 by kozy*

**physics**

Consider the rotational motion of two compact discs (CD). Disc A undergoes a rotation of 540 degrees in 1.50 secs, and disc B undergoes a rotation of π radians in 3.00 secs.
*April 7, 2014 by Anonymous*

**Physics**

Is the maximum torque that a given force can exert on an object occurs when the force is applied to the axis of rotation. I think it is true because torque is always specific when it comes to the axis of rotation. Am I correct?
*December 16, 2011 by David*

**physics**

A boy of mass 23 kg sits on a seesaw 1.5 m from the axis of rotation. At what distance from the axis of rotation must his friend, whose mass is 21 kg, be positioned to balance the seesaw? [6 marks]
*February 28, 2012 by alex*

**4th grade Science**

My daughter is learning translation and rotation in science right now...what is translation in regards to science?
*November 3, 2008 by Katie*

**Math**

Mr. Doodle’s grade distribution over the past 3 years for a course in college algebra is shown in the chart below. Grade Number A 45 B 180 C 110 D 95 F 65 I 5 If Jane plans to take a college algebra course with Mr. Doodle, determine the empirical probability that she receives ...
*July 19, 2011 by Jen*

**6 grade math**

Find 3 uppercase letters that look the same when rotated 180 degrees.Then,what letter's 90,180,270 degree rotations has this outline?This is also the inside lines formed by the rotation of what letter?
*January 6, 2010 by Victoria*

**Math**

A ferris wheel makes one rotation in 15 minutes. Find your car's location and the angle of rotation after: 3 mins., 5 mins., 9 mins., 12 mins. The diameter of the wheel is 328 ft. and the height, with the base, is 369 ft.
*May 14, 2012 by Ann*

**physics**

A ferris wheel makes one rotation in 15 minutes. Find your car's location and the angle of rotation after: 3 mins., 5 mins., 9 mins., 12 mins. The diameter of the wheel is 328 ft. and the height, with the base, is 369 ft.
*May 15, 2012 by Ann*

**Algebra**

Business Computers English Foreign Languages Health Home Economics Math Music Physical Education Science Social Studies GRADE LEVELS Preschool Kindergarten Elementary School 1st Grade 2nd Grade 3rd Grade 4th Grade 5th Grade 6th Grade 7th Grade 8th Grade High School 9th Grade ...
*October 9, 2014 by Anonymous*

**geometry**

What is the measure of the angle of rotation with respect to two lines that intersect to form a 45° angle? What is the measure of angle of rotation and how do you go about finding it when given an angle? Thanks for explaining
*January 17, 2010 by Sara*

**Math--Fast Pleasee!**

Find the coordinate of the image of the point (3,6) rotated with respect to the x-axis and the y-axis. I plotted the points and came up with (3,-6) and (-3,6) The choices for the answer is a)(6,-3) b) (-6,3) c) (-3,-6) d) (0,-6) Was I wrong or what did i do wrong? The point (3...
*May 7, 2007 by Emily*

**Math**

Mr. Doodle’s grade distribution over the past 3 years for a course in college algebra is shown in the chart below. Grade Number A 45 B 180 C 110 D 95 F 65 I 5 If Jane plans to take a college algebra course with Mr. Doodle, determine the empirical probability that she receives ...
*July 20, 2011 by Jen*

**c++**

Write a program that asks the user to input a grade that he or she received on an exam. The grade is an integer from 0 to 100 inclusive. The program should convert the numeric grade into the equivalent letter grade. Do the conversion by using a function Letter_Grade () that ...
*May 18, 2012 by jermaine*

**College Algebra**

Charlie can grade exams in 2 hours. It takes Mark 6 hours to grade the same exams. If they work together, how long will it take for them to grade the exams?
*March 30, 2011 by Devin*

**trigonometry**

what direction of rotation generates and angle with a measure of -90 degrees? of 120 degrees? what portion of a complete rotation is -90 degrees? 120 degrees?
*June 23, 2009 by nika*

**math**

Which transformation moves the figure from position A to position B? then it shows a picture of a heart like one thats facing u and the other one is sideways. is the answer a-rotation, b-reflection, c translation d-rotation and translation, i think its d also what does ...
*April 15, 2012 by Gabby ( 5 grade)*

**Physics**

a chain pulls tangentially on a 33.4kg uniform cylindrical gear with tension of 70.1 N. the chain is attached along outside radius at 0.794m from the axis of rotation. starting from rest gear takes 1.59 s to reach rotational speed of 1.08 rev/s. what is total frictional torque...
*May 10, 2011 by Jenna*

**3rd grade - Solor System**

Two Questions: If it takes Jupiter 9.9 hours to make one rotation around the earth. This means that one day on Jupiter is actually how long? This is as many as how many Earth days?
*February 21, 2010 by John*

**Physics**

A bike wheel rotates uniformly through 2 revolutions in 3 seconds. a) what is the period of the wheel's rotation? T=3rev/2s=1.5s b) what is the frequency of the wheel's rotation? (in Hertz) f=1/T =1/1.5 =.666Hz c) what is the angular speed of the wheel(provide answer in ...
*October 31, 2007 by Tammy*

**Trigonometry**

Find the angular speed in radians per sec. of the second hand on a clock. How long does it take for the second hand to make one rotation? And isn't one rotation 2pi radians? Let me know what you got as an answer.
*July 3, 2007 by James*

**Math**

Find equations for a pair of lines M and N so R(sub n)compose R(sub m) is the given transformation. A. The translation that maps the origin onto (5,0) B. The rotation of 180o about a point (Xo, Yo) C. The rotation of 40o about the origin D. The translation T with T(x,y) = (x+3...
*June 19, 2013 by Stace*

**physics**

A limb, which is 1m long, moves through an angle of 30 degrees in 0.5 seconds. a) What is the average angular velocity of: i) Its end? ii) A point 30 cm from the axis of rotation? b) What is the linear velocity of: i) Its end? ii) A point 30 cm from the axis of rotation?
*February 5, 2010 by Anonymous*

**physics**

A limb, which is 1m long, moves through an angle of 30 degrees in 0.5 seconds. a) What is the average angular velocity of: i) Its end? ii) A point 30 cm from the axis of rotation? b) What is the linear velocity of: i) Its end? ii) A point 30 cm from the axis of rotation?
*February 5, 2010 by Anonymous*

**physics !!**

A student on a stool rotates freely at 180 rounds per minute. The student holds a 1.00 kg mass in each outstretched arm, 0.8 m from the axis of rotation. The combined moment of inertia of the student and the stool is 6.00 kgm2 which remains constant. How far should the student...
*August 30, 2013 by kent*

**Chem**

A sample of 2-butanol has a specific rotation of 3.25. Determine the % ee and molecular composition of this sample. The sepcific rotation of pure (+)-2-butanol is +13.0. is it (3.25/13.0)x100%= 25%... i'm a little confused on the molecular composition though.
*November 18, 2008 by Jason*

**Algebra 1A**

From a base elevation of 8200 ft. a mountain peak in colorado rises to a summit elevation of 14588 ft. over a horizonal distance of 15842 ft. find the grade of the peak. The grade of the peak. The grade of the peak is %. Round to the nearest tenth as needed. Someone help ...
*October 8, 2009 by Don*

**Torque**

Which produces the largest torque? --->> 30.0 N perpendicular to the center of rotation at a radius of 1.5 m 30.0 N perpendicular to the center of rotation at a radius of 0.25 m 60.0 N perpendicular to the center of rotation at a radius of 1.0 m 60.0 N perpendicular to ...
*January 15, 2015 by Berny*

**ece**

Studies of children throwing have revealed that two- and three-year-olds A. throw while stepping forward with the opposite foot. B. throw with body rotation and full arm range. C. are unable to throw a ball of any size. D. throw mainly with their forearms, and little or no ...
*April 12, 2013 by Anonymous*

**organic chemistry**

A sample of 2-butanol has a specific rotation of -9.75 degrees. Determine the % ee (enantiomeric excess) and the molecular composition of this sample. The specific rotation of pure (+)-2-butanol is +13.0 degrees.
*November 15, 2008 by Jenn*

**Math**

Determine whether a regular decagon has reflection symmetry and/or rotational symmetry. If it has reflection symmetry, state the number of axes of symmetry. If it has rotation symmetry, state the angle of rotation. Explain how you determined your answers
*October 25, 2012 by Mae*

**Chem**

How do I estimate the optical roation of an (S)-enantiomer if I know the optical rotation to the (R)-enantiomer? For instance, for limonene, after conducting an experiment, I got that the optical rotation for the (R)-enantiomer was 10, would the (S) be -10? Any help would be ...
*October 2, 2007 by Jenny*

**9th grade algebra/Ms Sue**

Okay Ms. Sue. I am in 8th grade but I am taking Algebra with 9th graders. I am very confused with my previous problem. I have asked my Dad but we are both getting confused. Now I have come up with 22. Is this my correct answer?
*August 22, 2012 by Reed*

**Math Lit **

In a school there are 122 grade 8s, 105 grade 9s, 134 grade 10s, 109 grade 11s, 90 grade 12s. Express Each Class as a percentage of the whole school.
*February 5, 2012 by Thabo*

**physics**

The 20-g centrifuge at NASA's Ames Research Center in Mountain View, California, is a horizontal, cylindrical tube 58 ft long and is represented in the figure below. Assume an astronaut in training sits in a seat at one end, facing the axis of rotation 29.0 ft away. Determine ...
*October 15, 2012 by Ania *

**physics**

The 20-g centrifuge at NASA's Ames Research Center in Mountain View, California, is a horizontal, cylindrical tube 58.0 ft long and is represented in the figure below. Assume an astronaut in training sits in a seat at one end, facing the axis of rotation 29.0 ft away. ...
*September 10, 2013 by ler*

**physics**

I'm working on my science fair project for 5th grade. I want to measure the speed of rotation from an Ice skater. What type of equipment would I need to use? I think a video camera, a bright dot on the skater's chest and some type counter software. That's where I'm really stuck.
*November 8, 2014 by Maria D*

**Physics**

The Earth has an angular speed of 7.272·10-5 rad/s in its rotation. Find the new angular speed if an asteroid (m = 3.45·1022 kg) hits the Earth while traveling at a speed of 4.41·103 m/s (assume the asteroid is a point mass compared to the radius of the Earth) in each of the ...
*November 8, 2012 by Joe Frank*

**english**

- Computers - English - Foreign Languages - Health - Home Economics - Math - Music - Physical Education - Science - Social Studies GRADE LEVELS - Preschool - Kindergarten - Elementary School - 1st Grade - 2nd Grade - 3rd Grade - 4th Grade - 5th Grade - 6th Grade - 7th Grade - ...
*January 8, 2010 by peter*

**Geometry**

A car tire rotates when you drive. How is this type of rotation different from a rotation in Geometry? What other type of transformation is happening to the car tire? Thanks!
*March 11, 2014 by Ismary*

**science**

does jupiter have a clockwise or counterr-clockwise rotation? Both. It depends on the direction you are looking. For instance, looking at the Earth, from the South of Earth, Earth has clockwise rotation. But looking at it from the North, is is counterclockwise.
*May 27, 2007 by carol*

**physics**

A solid cylinder of mass 20 kg rotate about its axis of rotation with angular speed 100m/s. The radius of the cylinder is 0.25m. What is the K.E. associated with the rotation of the cylinder what is the magnitude of the angular momentum of the cylinder about its axis
*March 16, 2013 by shubham mahur*

**Physics**

Here's the question again that I am trying to get help with because I can't figure it out and I got one answer, but I really couldn't understand it. Help please! A ferris wheel makes one rotation in 15 minutes. Find your car's location and the angle of rotation after: 3 mins...
*May 16, 2012 by Ann*

**Science**

Describe how the rotation of Earth is responsible for the movement of the stars. The rotation of earth is responsible for the movement of stars because as it rotates, objects around it rotate as well, such as planets, they appear to move through the stars because they are that...
*February 5, 2010 by Sara*

**Science-Repost**

Describe how the rotation of Earth is responsible for the movement of the stars. The rotation of earth is responsible for the movement of stars because as it rotates, objects around it rotate as well, such as planets, they appear to move through the stars because they are that...
*February 6, 2010 by Sara*

**Algebra**

Alma can grade a batch of placement exams in 3hr and Kevin can grade a batch in 4hr. if they work together to grade a batch of exams, what percentage of the exams will have been graded by Alma?
*May 24, 2014 by Kgk*

**Math**

Jessie’s average grade in Algebra for the first two terms is 73.5. What grade must he get in the third term to have an average of 75?
*October 17, 2012 by Milen*

**MATH**

there are 400 students at smith Elementary school 1/4 of the students are in fourth and fifth grade, 1/10 of the students are in grade 3, 2/8 are in second grade and 2/5 are in first grade . How many kids are in each grade? (4th and 5th have an equal amount)
*March 24, 2014 by MANISH*

**Chemistry**

A sample of 2-methyl-1-butanol has a specific rotation of -3.25°. Pure (R)-2-methyl-1-butanol has a specific rotation of +5.75°. Determine the %ee and molecular composition of the sample.
*March 2, 2010 by Chad*

**math**

I have a question I would really appreciate the answer. If 15% of my grade is 74% and 96 is 15% of my grade and 40% of my grade is a 60.5% without the final counting for 30% what is my grade? Please help thank you.
*June 26, 2015 by kim*