Friday

May 29, 2015

May 29, 2015

Total # Posts: 4,040

**physics**

A stone tumbles into a mineshaft and strikes bottom after falling for 4.2 seconds. How deep is the mineshaft?
*November 29, 2011*

**physics**

A water balloon was dropped from a high window and struck its target 1.1 seconds later. If the balloon left the person’s hand at –5 meters/sec, what was its velocity on impact?
*November 29, 2011*

**chemistry**

what must be done with the radioactive waste materials that result from splitting atoms and how is this a problem?
*November 14, 2011*

**Astronomy **

The distance between the Earth and Mars when the two panets are at opposition varies greatly because of the large eccentricity of Mar's orbit. The perihelion distance of a planet is given by rmin=a(1-e)and the aphelion distance by rmax=a(1+e) where a is the semimajor axis ...
*November 14, 2011*

**biology**

another way to afect the enzyme is lowering the pH of the solution. However, lactase is supposed to be able to work in the stomack. Would lowering the pH of the enzyme solution affect the enzyme? Why or why not?
*November 11, 2011*

**Western Civ**

Help! Describe the evolutionary account of the emergence of Israelite religion paying particular attention to the ideas of covenant, law, prophets, morality, relations with Canaanite culture, and other themes you deem significant. Also explain how Jewish scripture was put ...
*November 9, 2011*

**6th grade ELA**

nnnnnnnoooooooooooooo
*November 8, 2011*

**writing**

Mother sewed fur jackets for Father and me
*November 8, 2011*

**writing**

how do you do that? that's what I dont get?
*November 8, 2011*

**writing**

is this a correct way to write this sentence Mother sewn fur jackets for Father and I, just in case the weather gets bad. thank you!
*November 8, 2011*

**writing**

its an exploration narrative journal im writing about seeing the grand canyon for the first time
*November 8, 2011*

**writing**

is there another way to rephrase this sentence in a good way. --- All I ever heard about this Grand Canyon thing was that it is piled up with humongous rocks and composed of fossils. thank you!
*November 8, 2011*

**Calculus**

Thanks Steve.
*November 7, 2011*

**Calculus**

Please help me with the following 2 questions. 1. Find the area of the curved surface of a right-circular cone of radius 6 and height 4 by rotating the straight line segment from (0,0) to (6,4) about the y-axis. 2. Use the Maclaurin polynomial of degree 4 to approximate sin(0....
*November 7, 2011*

**math- precalculus**

Help please! I can't seem to get x as the answer to prove that they are inverses of each other! Show what f and g are inverse functions algebraically f(x)= x-1/x+5 g(x)= -5x+1/x-1
*November 4, 2011*

**Algebra 1**

What is the answer to 10-3x is less than or equal to 7x? I tried the problem, but I keep getting x is less than or equal to 1. Is that right?
*November 3, 2011*

**Math**

8,9,11,14 , , ,
*November 2, 2011*

**Statistics**

Suppose that a sample of 50 scores has a mean of Y=90 and the standard deviation is 15. Between what two values of Y will at least 90% of the scores fall? What is the maximun number of scores that can lie out of the interval?
*October 30, 2011*

**Physics**

It is impossible to have a collision between two objects in which the center-of-mass of the system is stationary the entire time. False If the magnitude of the momentum of one object is smaller after the collision than it is before the collision, the magnitude of the momentum ...
*October 29, 2011*

**chem**

Complete the table below: Note: Make simplifying assumptions, do not use the quadratic formula. What is the pH of the solution created by combining 11.80 mL of the 0.10 M NaOH(aq) with 8.00 mL of the 0.10 M HCl(aq)? with 8.00 mL of the 0.10 M HC2H3O2(aq)? Complete the table ...
*October 28, 2011*

**chemistry**

Complete the table below: Note: Make simplifying assumptions, do not use the quadratic formula. What is the pH of the solution created by combining 2.00 mL of the 0.10 M NaOH(aq) with 8.00 mL of the 0.10 M HCl(aq)? with 8.00 mL of the 0.10 M HC2H3O2(aq)? Complete the table ...
*October 28, 2011*

**Math algebra**

how do you do this by using the FOIL method? 1. 3x^2 + 22x + 7= 2. 2x^2 + 5x - 12= 3. x^2 - 11x + 28= thank you!
*October 26, 2011*

**world history**

3 contributions of fancois rabelais
*October 23, 2011*

**geometry**

line rs intersects line lm at p, angle rpl=x+y, lps=3x+2y, mps=3x-2y. solve for x and y find angle RPL, LPS, and MPS
*October 23, 2011*

**geometry**

line MN is perpendicular to op If the coordinates of M,N and O are (2,4), (-5,-8) , (-6,2) respectively, find the equation for line OP
*October 23, 2011*

**geometry**

what is the perimeter of triangleABC if the coordinattes of A,B and C are (3,7), (7,3) and (-2,5) respectively
*October 23, 2011*

**Physics**

A projectile is fired with an initial speed of 28.0 m/s at an angle of 65 degrees above the horizontal. The object hits the ground 9.5 seconds later. a) How much higher or lower is the launch point relative to the point where the projectile hits the ground? b) To what maximum ...
*October 19, 2011*

**CALCULUS ONE!**

The graph of sinx and cosx intersect once between 0 and pi/2. What is the angle between the two curves at the point where they intersect? (You need to think about how the angle between two curves should be defined).
*October 18, 2011*

**Chemistry**

You have 250 mL of a 0.80 M solution of silver nitrate AgNO3 (169.87 g/mol) dissolved in water. How many grams of AgNO3 does the solution contain?
*October 17, 2011*

**philosophy**

how did existentialism fail?
*October 13, 2011*

**Chemistry**

completely dissolved-KNO3, NaNO3, Pb(NO3)2 partially dissolved-KCl, KClO3, K2Cr2O3
*October 11, 2011*

**Physics**

Let vector A = 4i^ + 4j^, vector B = -2i^ - 5j^, and vector F = vector A - 5(vector B). a) Write vector F in component form. vector F = ? b) What is the magnitude of vector F? F = ? c) What is the direction of vector F? theta = ? Thank you!
*October 10, 2011*

**Physics**

Let vector A = 4i^ + 4j^, vector B = -2i^ - 5j^, and vector F = vector A - 5(vector B). a) Write vector F in component form. vector F = ? b) What is the magnitude of vector F? F = ? c) What is the direction of vector F? theta = ? Thank you!
*October 8, 2011*

**H.W in Partial economy **

Bundle** Oranges/Week ** Total Utility A 0 50 B 1 80 C 2 100 D 3 115 E 4 125 F 5 133 G 6 139 H 7 144 I 8 146 J 9 147 K 10 147 L 11 147 M 12 147 N 20 147 From the above table draw TU curve and MU curve find MU when using the fourth oranges, then derive the demand line
*October 7, 2011*

**big lake**

Two cyclists, 36 miles apart, start riding toward each other at the same time. One cycles 2 times as fast as the other. If they meet 2 hours later, what is the speed (in mi/h) of the faster cyclist?
*October 6, 2011*

**Physics**

Tim and Rick both can run at speed Vr and walk at speed , Vw with Vr > vw. They set off together on a journey of distance . Rick walks half of the distance and runs the other half. Tim walks half of the time and runs the other half. How long does it take Tim to cover the ...
*October 5, 2011*

**grammar**

need to know some examples for the nominative comparative and superlative of irregular words apart from good better best , bad worse worst and little less least
*October 5, 2011*

**science**

what is a machine?
*October 4, 2011*

**us history**

thanks!
*October 3, 2011*

**us history**

Im doing a crossword and im stuck on the last one. the topic is immigration and urbanization. 1. neighborhoods on the outskirts of a city..?
*October 3, 2011*

**government **

hey i need help in this question Is there ever a time where american citizens disagreed with the way the government is handling things in the past?
*October 3, 2011*

**math**

Allyson and Adrian have decided to connect their ankles with a bungee cord; one end is tied to each person's ankle. The cord is 30 feet long, but can stretch up to 90 feet. They both start from the same location. Allyson moves 10 ft/sec and Adrian moves 8 ft/sec in the ...
*October 1, 2011*

**Math**

Yes, it is the inverse hyperbolic sin.
*September 29, 2011*

**Math**

Let f(x)=sinh^−1(6x). Then f(x) can be written in the simplified form (Ax+B)/(sqrt(Cx^2+D). What are the values of A,B,C and D? Again, please show me how to do this. Thanks
*September 29, 2011*

**Math**

Let f(x)= (sqrt(25−x^2))+5 arccos (x/5). Then f(x) can be written in the simplified form − [(x+c)/mx+n)]^p. What are the values of c,m,n and p? Please tell me how to do this question. Thanks
*September 29, 2011*

**help plesse :)**

the answer is B
*September 29, 2011*

**math**

What is 6% sales tax on $2.59
*September 29, 2011*

**math**

A class of 25 students has 10 boys. Three boys have braces and 4 girls have braces. a) What is the ratio of boys with braces to boys in class? b) What is the ratio of girls with braces to girls in class? c) Which group has the largest ratio of students with braces to students ...
*September 29, 2011*

**Calculus 2**

The question is: Evaluate the improper integral for a>0. The integral is: the integral from 0 to infinity, of e^(-y/a)dy Can anyone help me solve this? When I try I get 'a', which apparently is incorrect. Thank you!
*September 25, 2011*

**Chemistry **

Thank you Doctor Bob this helped a lot i got the answer so i must have done something right :)
*September 25, 2011*

**Chemistry **

NO2 + NO = N2O3 Inital concentration 2.0, 2.0, 0 Change concentration , ,2.5 Equilibrium concent. , ,2.5
*September 25, 2011*

**Chemistry **

For the reaction NO2(g) + NO(g) = N2O3(g) If at particular temperature, K was 575 and equilibrium concentration of N2O3(g) was 2.5 M, calculate the equilibrium concentrations of NO2(g) and NO(g) if they both had the same initial concentrations. i have my table layed out like...
*September 25, 2011*

**algebra**

how do you substitute these system of equations 1.y=-3x-3 y=3x-3 2.y=4x-6 y=x thank you!
*September 23, 2011*

**Language**

b) Sketch d) crutch f) stretch That all i could get
*September 22, 2011*

**Chemistry**

I don't understand one of my homework questions i'm really stuck. please help! How will the equilibrium: Heat + CH4(g) + 2H3S(g)= CS2 (g) + 4H2 (g) be affected by the following: a) A decrease in temperature. b) The addition of H2. c) The removal of some CH4 (g) d) An ...
*September 22, 2011*

**Chemistry**

I don't understand one of my homework questions i'm really stuck. please help! How will the equilibrium: Heat + CH4(g) + 2H3S(g)= CS2 (g) + 4H2 (g) be affected by the following: a) A decrease in temperature. b) The addition of H2. c) The removal of some CH4 (g) d) An ...
*September 22, 2011*

**algebra!**

how do you solve this by substitution: step by step 1. 5x-y=16 5x+2y=13 2. 3x-3y=9 2x-4y=-16 3. x=-6y y=2/3x+5 thank you!
*September 20, 2011*

**Math**

how do you solve this by substitution: step by step 1. 5x-y=16 5x+2y=13 2. 3x-3y=9 2x-4y=-16 3. x=-6y y=2/3x+5 thank you!
*September 20, 2011*

**geometry!**

can anyone please explain to me how to solve these problem step by step: 1. 3x+y= -6 2. 2x-5y=12 thank you!
*September 19, 2011*

**Math**

PS sin is raised to the power of 3, so it's sin^3 x.
*September 19, 2011*

**Math**

If f (x) = sin3 x, find f'(x). Find f'(−2pi/3) Thanks.
*September 19, 2011*

**Math**

1. Evaluate the indefinite integral integral symbol[6x5+2sec(x) tan(x)]dx. 2. Integral symbol 8 at the top, 5 at the bottom 3x2+3x2 dx = Thanks
*September 19, 2011*

**US history**

what do you think are the top major events between 1850-1877? thanks
*September 18, 2011*

**math riddles**

Trying to find a porking place
*September 17, 2011*

**math riddles for 7th grade**

Trying to find a porking place
*September 13, 2011*

**science**

sugar is one of the main sources of what for cells
*September 10, 2011*

**science**

sugar is one of the main sources of what for cells
*September 10, 2011*

**english**

I am having a hard time coming up with a theme for the book "Once upon a town" can someone help me?
*September 9, 2011*

**calculus**

When you have a function that changes direction several times, how do you determine the interval over which the function is decreasing?
*September 7, 2011*

**math**

sorry typed that rong its supposed to be 2 cubed
*September 7, 2011*

**math**

the derections are: Add parenteses so that each equation is correct. 2squared+6-5*4=12
*September 7, 2011*

**u.s history**

my question kind of has 2 parts. first off i am trying to put in order what i think are the 10 most important things that happened between 1800-1850's does any one have any idea what they might be? also. What presidents where president between the 1800-1850 and what order ...
*September 7, 2011*

**trig**

log(x-15)-2=-logx
*September 6, 2011*

**trig**

Okay, thanks :)
*September 6, 2011*

**trig**

But the question above is loga+logb=loga*b
*September 6, 2011*

**trig**

log4+log(x-7)=2
*September 6, 2011*

**math**

0.013 x 10^3
*September 6, 2011*

**chemistry**

Determine how much heat is evolved or absorbed when 40.0 g of lithium iodide completely dissolves in water.
*September 5, 2011*

**math**

A movie theater seats 500 people. For any particular show, the amount of money the theater makes is a function m(n) of the number of people, n, in attendance. If a ticket costs 2 dollars, find the domain and range of this function. domain: ?≤ n ≤? range: ?≤ m...
*September 3, 2011*

**Geometry**

Find the perimeter of a triangle where the area equals 27 and the height is 3 times the length?
*August 31, 2011*

**u.s history**

thanks!
*August 29, 2011*

**u.s history**

I have a test tomorrow in US history that I am studying for. My teacher told us that on the test we will have to put 10 of the most important and relavent things that happened from prehistory to 1824. I have a hard time learning history. I know the first and last thing she ...
*August 29, 2011*

**psychology**

Not asking to do my work for me, this is the question. I am cunfused to what therory makes personality? Did ask for attitude asked for help!
*August 29, 2011*

**psychology**

1.Once you have read about the major perspectives in psychology, identify any questions you have about these seven major theories (psychodynamic, behavioral, humanistic, cognitive, Biopsychological, Evolutionary, Sociocultural). You must come up with at least one question ...
*August 29, 2011*

**explain the difference between muslims and arabs**

Muslim is a religion, wheras arab is like a nationality.
*August 28, 2011*

**Precalc**

ohhhh wooow why didnt i think of it that way haha thanks!
*August 21, 2011*

**Precalc**

why wouldnt it be cos(theta-20)/2?
*August 21, 2011*

**Precalc**

Then how would i bring the r out?
*August 21, 2011*

**Precalc**

How would you simplify this polar equation to r=? 2=rcos(theta-20) Would i divide the 2 by both sides?
*August 21, 2011*

**Precalc**

Identify the graph of the equation. What is the angle of rotation for the equation? y^2+8x=0 is parabola 90 degrees correct? also Identify the graph of the equation. What is the angle of rotation for the equation? xy = -5 =hyperbola 45 degrees
*August 21, 2011*

**Precalc**

Write the equation of the hyperbola whose center is at the origin and has a vertical transverse axis. The equations of the asymptotes are 6x + 2y = 0 and 6x - 2y = 0. Is this correct? (y^2/9)-(x^2/4)=1
*August 21, 2011*

**Precalc**

okay thanks!
*August 21, 2011*

**Precalc**

Write the equation in standard form of the ellipse with foci (8, 0) and (-8, 0) if the minor axis has y-intercepts of 2 and -2. is the answer: x/64+y/4=1
*August 21, 2011*

**Math**

.4 is not the right answer.
*August 20, 2011*

**chemistry**

N204 (l) Delta Hf (kJ/mol) = -20 E cell S (J/mol.K) = 209 N204(g) Delta Hf (kJ/mol) = 10 E cell S (j/mol.k) = 304.1 Given the following data, determine the temperature at which n2o4 (l) and n204 (g) can exist in equilibrium? a. 42 C b. 3 C c. -231 C d. 30 C e. -178 C
*August 17, 2011*

**math**

what is the largest negative coterminal angle of -417?
*August 16, 2011*

**english **

thank you
*August 7, 2011*

**english **

can anybody help me know negative reasons i have allot of positive
*August 7, 2011*

**english **

its not really giving any negative reasons
*August 7, 2011*