Saturday

April 30, 2016
Total # Posts: 325

**Physics**

An object is placed 18m from a screen. At what points between the object and the screen may a lens with focal length of 4m be placed so that an image can form on the screen. I have an exam in a few days, and this is one example my prof never really explained, he just stated. ...
*April 18, 2016*

**Chemistry**

Which must be the same when comparing 1 mol of oxygen gas, O2, with 1 mol of carbon monoxide gas, CO?
*April 14, 2016*

**Algebra**

Sorry Steve, I miscopied the data, the x values for weeks 2 and 3 week 2 is actually 300 on sales and week 3 is 700 on sales, my bad
*April 12, 2016*

**Algebra**

Michael's total weekly pay includes a base salary plus certain percent of his sales. The table below show Michael's sales for 4 weeks and his total weekly pay. This data represents a linear function. What is Michael's weekly base salary? Sales (x)week 1: $800 week ...
*April 12, 2016*

**Vectors, Math**

A is (3, 2) and point B is 4 units from A in the direction (1,-1) Find AB(arrow). Find the coordinates of B. I can't do this question, Ive attempted it many times.
*April 11, 2016*

**Math**

Search up how to solve simultaneous equations. Substitution/ elimination method
*April 8, 2016*

**Algebra**

Hi guys, Im doing algebraic fractions and I got this fraction: (x^2+2x+1)/(x^2+1) , but the answers say that this is correct: (x^2-1)/(x^2-2x-1). So is (x^2+2x+1)/(x^2+1) = (x^2-1)/(x^2-2x-1)? Thanks in advance
*April 4, 2016*

**Algebra**

Use pythagoras, a^2+b^2=c^2 a=12, b=5
*April 4, 2016*

**Chemistry**

thanks @DrBOb222 :)
*March 28, 2016*

**Chemistry**

A sample of calcario and other components of the soil was intensely warm. Under these conditions, the calcario undergoes decomposition in calcium oxide and carbon dioxide. CaCO3 (s)-> CaO (s) + CO2 (g) The analysis of 71, 42 g of a sample of limestone supplied 13 g of ...
*March 28, 2016*

**physics**

3 equal charges each of of 2*10-6 C are fixed at three corners of an equilateral triangle ofsides 5 cm.find the column force experienced by one of the charge due to the other two
*March 23, 2016*

**physics**

3 equal charges each of of 2*0.000001C are fixed at three corners of an equilateral triangle ofsides 5 cm.find the column force experienced by one of the charge due to the other two
*March 23, 2016*

**Math**

Fit the rule: AEFHIKLMN. Did not fit the rule: BCDGJOP.What is the rule?
*March 22, 2016*

**Calculus**

Steve you plug the x value into the y formula which causes you to add 1 to the even value... always check your work.
*March 15, 2016*

**chemistry**

A 1L flask contains 0.2moles of air open to atmosphere at 0degree celcius. Upon heating some of the air is lost. What is the percentage of air remaining in the flask?
*March 13, 2016*

**Life orientation**

3 corses or study fields you are interested in following after grade 12
*March 5, 2016*

**Math**

A three-strand wire fence around a square 40-acre parcel would require how much wire?
*February 25, 2016*

**Math**

A road runs along the south boundary of the SW 1/4 of the SW 1/4 of a section. If the road contains two acres in the area, the width of the road would be: The answer is 66 feet, but I can't calculate it.
*February 25, 2016*

**math**

Develop a unit of learning at the end of which learners should be able to: reduce any angle in the first quadrant of a Cartesian plane to a difference of 90 and an acute angle. I have tried it as follows: 1. write down any three acute angles. 2. draw the angles in a Cartesian ...
*February 18, 2016*

**chemistry**

using the Kw for pure water, show that: pH = pKw - pOH
*February 9, 2016*

**math**

the area of the pool is 108m. what is the length of the pool if it is 9m wide
*February 9, 2016*

**Math**

the questions says if carlos eats 1/2 icream every night for dessert. He has 3 cups left. How many days can he eat a 1/2 cup before running out. How do I solve this problem
*February 3, 2016*

**Chemistry**

Consider that: the tetravalent cation of an isotope has 78 electrons and 128 neutrons; Nuclear relative mass of the same cation is 1.44% higher than the relative nuclear mass of its most common isotope based on these data, calculate the number of neutrons isotope
*January 26, 2016*

**Chemistry**

Consider that: the tetravalent cation of an isotope has 78 electrons and 128 neutrons; Nuclear relative mass of the same cation is 1.44% higher than the relative nuclear mass of its most common isotope based on these data, calculate the number of neutrons isotope.
*January 26, 2016*

**Math**

math puzzle: i am less than 3000. all four digits are odd. all four digits are different. the sum of my tens digit and ones digit is 16. i am divisible b 13. who am i? Ans: the thousand digit must be 1, the hundreds digit is 3 or 5. The tens and ones digits are 9,7 or 7, 9. So...
*January 19, 2016*

**united staes history**

what generalization can you make about the abolition of slavery in the north?
*January 15, 2016*

**Math**

Fred needs a piece of plywood 39in. by 23in. he cut it out of a piece that was 4ft. by 8ft.What is the area in square inches of the piece that was left?
*December 9, 2015*

**math**

A cyclinder cooling tank has an outside diameter of 6.00 ft. the wall on all sides are 5.00in thick and the tank is 10.0ft tall. how many gallons of water will this tank hold?
*November 13, 2015*

**math**

A cyclinder cooling tank has an outside diameter of 6.00 ft. the wall on all sides are 5.00in thick and the tank is 10.0ft tall. how many gallons of water will this tank hold?
*November 12, 2015*

**math**

A rectangle piece of gold has dimensions 0.3125in. by 18.0in by 15.0 in what is its total surface area? if gold weighs 0.698lb/in3, determine its weight.
*November 12, 2015*

**tech math**

Each cylinder bore of a cylinder engine has a diameter of 2.50in. and a height of 4.90 what is the combined total surface area of all four cylinder?
*November 12, 2015*

**Trig application**

I can't figure this out. A famous golfer tees off on a long, straight 459 yard par 4 and slices his drive 10 degrees to the right of the line from tee to the hole. If the drive went 288 yards, how many yards will the golfer's second shot have to be to reach the hole?
*October 29, 2015*

**Science**

What is the average for 4cm 5cm and 5cm
*October 19, 2015*

**Chemistry - Radioactivity**

The activity of a sample of Ba-137m has decreased by 75% from its initial activity after 5.10 minutes. What is the half-life of Ba-137m? What fraction of activity remains after 6.25 minutes? (A=Aoe (-kt); k = .693/t1/2)
*September 27, 2015*

**math**

Train #1 leaves san diego at 4pm. train #2 leaves san diego at 6pm.train #2 travels 42 mph faster than train #1. if train # 2 overtakes train #1 at 8pm, what is the speed of each train?
*September 17, 2015*

**math **

Please I need help with this problem. it took us 3 hour to drive to a concert.on his way home he increased his speed by 19 miles got home in 2 hours . what was the speed? thank you
*September 16, 2015*

**pre algebra**

hank you Reiny.
*September 16, 2015*

**pre algebra**

it took us 3 hour to drive to a concert.on his way home he increased his speed by 19 miles got home in 2 hours . what was the speed
*September 16, 2015*

**geometry**

The endpoints of are A(2, 2) and B(3, 8). is dilated by a scale factor of 3.5 with the origin as the center of dilation to give image . What are the slope (m) and length of ? Use the distance formula to help you decide: .
*September 11, 2015*

**Pre-ALgreba**

13.2
*September 10, 2015*

**Algebra**

The measure of the smallest angle of a triangle is one-fourth the measure of the largest angle. The measure of the second angle is 36 less than the measure of the largest angle.
*August 31, 2015*

**Maths pure, economics, business studies, geography **

Which careers or courses i should do doing those subjects
*August 8, 2015*

**Mathematics , business studies , economics , geography **

Which courses or careers i should follow doing those subjects
*August 8, 2015*

**Algebra 1**

thank you for all the help
*May 31, 2015*

**Algebra 1**

A right triangle has 1 leg that is 2" longer than the other leg. the length of the hypotenuse is sqrt 130" Find lengths of legs 0=2x^+4x-126
*May 31, 2015*

**Algebra**

The legs of an isosceles triangle are 0.3 foot less than twice the base. The perimeter of the triangle is 4.9 feet. What is the length of one of the triangle’s legs?
*May 1, 2015*

**Child Development**

Research has shown that most preschool A.don't use the words "think,"remember or pretend c. believe that an event can be known without being directly observes. D. often insist they've always known information they just learned
*March 11, 2015*

**Physics**

Calculate the energy released when 235 U fissions resulting in two lighter stable nuclei with mass numbers 140 and 93.Please help!
*March 4, 2015*

**Physics**

I used this equation: Change in x = (velocity^2/2*mu*gravity)
*February 11, 2015*

**Math**

A giant pumpkin is 90% water and weighs 250 pounds. The pumpkin is placed on display as the largest pumpkin of the year at the LA county fair. During the week-long fair, the pumpkin loses water from being outside in the heat. At the end of the week, the pumpkin is only 80% ...
*February 10, 2015*

**chemistry**

i want to neutralize a 10 ml 3 molar sulfuric acid using calcium carbonate but don't know how to do the math the explanation confused me. (also i have to use sig fig and uncertainty)
*February 10, 2015*

**chemistry**

How many grams of calcium carbonate would it take to neutralize if i have 10ml 3 molar sulfuric acid? (can this be explained in detail?)
*February 10, 2015*

**chemistry**

i think you meant carbonate not bicarbonate
*February 10, 2015*

**History Help?**

What role did Stephen Austin play in the settlement of Texas by American colonists? He defeated Santa Anna's army, making it safe for colonists in the region. He convinced American colonists in Texas to declare their independence from Mexico. He received a large land grant...
*December 1, 2014*

**Maths**

The nth term of a series is 2^n-1 +5n. Find the sum of the first n terms. (Hint: This is an expression in terms of n).
*December 1, 2014*

**Math (Can someone Help)**

The temperature was 48.2° when Marcy went to bed and 35.7° when she woke in the morning. What was the change in temperature? A: 83.9° B: 82.5° C: 13.5° D: 12.5° < -- ? Carlos bought 3 gallons of ice cream for $9.50. Which proportion can be used to ...
*November 13, 2014*

**Math *checking answers*?**

Yeah I noticed that, but I didn't pick either because they were the same. Thank you(:
*November 13, 2014*

**Math *checking answers*?**

The temperature was 48.2° when Marcy went to bed and 35.7° when she woke in the morning. What was the change in temperature? A: 83.9° B: 82.5° C: 13.5° D: 12.5° < -- ? Carlos bought 3 gallons of ice cream for $9.50. Which proportion can be used to ...
*November 13, 2014*

**Statistics**

In a population, heights of males are normally distributed with u=180 cm and sigma^2=16 cm^2, while the heights of females are normally distributed with u=170 cm and sigma^2= 25 cm^2. a) One random male and one random female are selected from the population i)What is the ...
*November 9, 2014*

**Art**

1. Why would an artist chose to use harmony in a piece of artwork? 2. Perspective drawings will utilize all methods listed here except? 3. To create an image that is not harmonious, an artist could...?
*November 3, 2014*

**Gramma**

To Ms. Sue: Thank you very, very much for your help.
*October 28, 2014*

**Gramma**

Ms. Sue please check this complex sentence. The high school band became ebullient upon recieving the news that they won first place in the band competition.
*October 28, 2014*

**Gramma**

Although his political campaign was fallacious, the people voted for him anyway. Ms Sue please check this thank you.
*October 28, 2014*

**Gramma**

How can I use the word fallacious in a complex sentence?
*October 28, 2014*

**English**

How is the word brusque used in a complex sentence? please give examples.
*October 28, 2014*

**physics**

A cable with 24.0N of tension pulls straight up on a 1.02kg block that is initially at rest What is the block's speed after being lifted 2.20m ? Solve this problem using work and energy. Express your answer with the appropriate units.
*October 26, 2014*

**physics**

why is it that drivers place cement blocks and other heavy items in the trucks of their vehicles? (think of friction and normal force)
*October 24, 2014*

**English**

@ words : 1- curtail 2- devastate 3- digress 4- incentive 5- incorporate 6- indispensable 7- intermittent 8- rigor 9- squander 10-succumb Linda never had to work hard to make good grades in high school. But in college, where the ___(8)___ of course work were greater, she soon ...
*October 23, 2014*

**math**

1/7 will be the ans
*October 20, 2014*

**math**

2/3 = 14/21 21-14-4 = the # of the beads left that # = 3 so 3 bead should be white
*October 20, 2014*

**Pre-Calc**

cuz you know that the angle is in the top left you can use tan(x) = y/x to calculate the angle(it must be bigger than 90) than use cos(x) on your cal to find cos(x) or you can use x^2 + y^2 = hyp^2 to find the hyp and do (-1/5)/(hyp length) to get cos(x)
*October 20, 2014*

**physics**

change in KE = 1/2 mv2^2 - 1/2mv1^2 = 1/2m(v2^2-v1^2) where v2 and v1 are the final and initial speeds 242 = KE plug in numbers to get ans(mass) :D
*October 20, 2014*

**Physics**

This is a question related to work. Today we had a pop quiz in my physics class and I am just trying to check my work here :D 1) if there is a 5 kg block on a horizontal table connected with string to a 3 kg block hanging off the side of the table through a pulley. Assume the ...
*October 20, 2014*

**math**

Okay if you submitted those answers you made a 50 like me. but i suppose thats what i get right. The answers are actually B A D B
*October 14, 2014*

**Finance**

Your program has a proposed RDT&E-funded project scheduled to start in January 2015 which is expected to take 16 months to complete. The project is expected to cost a total of $16 million (then-year dollars), with cost expected to be incurred at a rate of $1 million per month...
*October 8, 2014*

**math**

Suppose that a crayon weighs the same as a marker. You have a box of crayons, 4 extra crayons, and 20 markers. Let b be the number of crayons in the box. A scale balances with all the crayons on one side and all the markers on the other. You remove markers from the scale so ...
*October 2, 2014*

**factorise completely**

2ax - 3ay + 2x - 3y
*September 20, 2014*

**chemistry**

An ore contains Fe3O4 and no other iron. The iron in a 65.46 gram sample of the ore is all converted by a series of chemical reactions to Fe2O3. The mass of Fe2O3 is measured to be 37.9 grams. What was the percent Fe3O4 in the sample of ore? Answer in units of %
*September 7, 2014*

**Math**

x =2(y+3) or y=3+1/2x
*September 4, 2014*

**chemistry**

At what angle (in degrees) must {111} planes of platinum (Pt) be exposed to a collimated beam of thee X-rays in order to obtain by diffraction monochromatic CrKα radiation.
*August 26, 2014*

**chemistry**

Gallium Arsenide ---------------- The charge carrier density of GaAs at 31o C is 2.25x106 cm-3. What is the charge carrier density (in cm-3) at 175oC? (The bandgap of GaAs is 1.42 eV. ) I am trying with arrhenius relationship but get confused over "charge carrier density&...
*August 25, 2014*

**chemistry**

Gallium Arsenide ---------------- The charge carrier density of GaAs at 31o C is 2.25x106 cm-3. What is the charge carrier density (in cm-3) at 175oC? (The bandgap of GaAs is 1.42 eV. )
*August 25, 2014*

**math**

Kendra bought 4 paintings and wants to hang them side by side on a wall in her bedroom. However, only 3 of the paintings will fit side by side on this wall. How many different ways can Kendra arrange 3 of the 4 paintings on the wall?
*July 31, 2014*

**Practical english**

Which of the following sentences contains an indefinite pronoun? A. This is Mary's necklace.
*May 1, 2014*

**English **

Hello I need some ideas to elaborate on in an essay about the following question "1.According to Frankenstein what makes the Creature more “human,” his weaknesses or his strengths?Why?" Now I believe it is his weaknesses but i dont know what Victor ...
*February 16, 2014*

**Beacon Height**

what is the time for the first clock
*January 9, 2014*

**EARTH SCIENCE**

number one is absolutly D i had gotten that one right.
*January 7, 2014*

**Lit**

What is a basic draft for a claim (Toulmin) about the theme. For example, "The theme of the piece is "blah-blah" " doesn't have an argument. What does?
*December 15, 2013*

**Math**

50 x 50 x 50 x 50
*December 15, 2013*

**English**

Fear not for these answers are still correct
*October 17, 2013*

**maths lite,life science,geography and tourism**

What career can I take
*October 3, 2013*

**Grammar Advisor**

Are these correct? I mark my answer with an X. 88. The reason to list all of the preliminary (non-procedural) information in a lesson plan is to be sure have considered each aspect. keep good records for your future needs. be able to communicate clearly with administrators, ...
*September 25, 2013*

**Grammar Advisor**

I just cannot figure out if these answers are correct or not. Can you please help me? 78. If the sound system hadn’t failed, last night’s show would have been better. This is a correct sentence using the 1st conditional form. x This is a correct sentence using the ...
*September 25, 2013*

**math**

what are the 5 number combo in 1 to 39
*September 8, 2013*

**Science**

Which of the following is an environmental concern of genetically engineered crops mentioned in your text? (Points : 1) Genetically modified crops lead to larger applications of toxic herbicides and insecticides. The genetic modification of crops increases soil erosion while ...
*August 21, 2013*

**math**

Joan receives an annual salary of $22,768.68. What is the total amount of her gross pay each period if she is paid monthly?
*August 14, 2013*

**math**

Erma is paid $516.72 biweekly. What are her annual earnings?
*August 14, 2013*

**math**

Sheila received a 6.5% commission on a house she sold for $110,400. How much commission did she receive?
*August 14, 2013*

**american history**

Under the _______ system, Spanish conquistadors were rewarded with local villages and control over the local labor force
*July 15, 2013*

**math **

Explain whether the following statement is true or false: “The ordered pair (1,5) is the same as the order pair (5,1).”
*July 2, 2013*