# W

Most popular questions and responses by W
1. ## chemistry

The chemical analysis of aspirin indicates that the molecule is 60.00% carbon, 4.44% hydrogen, and 35.56% oxygen. What is the emperical formula for asprin?

asked on January 20, 2010
2. ## Chemistry

2 B5H9(l)+12 O2(g)---->5 B2O3(s)+9 H2O(l) Calculate the kilojoules of heat released per gram (kJ/g) of the compound reacted with oxygen. The standard enthalpy of formations of B5H9(l), B2O3(s), and H2O(l) are 42.84, -1271.94, and -285.83 kJ/mol,

asked on November 1, 2010
3. ## Physics

Sam, whose mass is 71.0 kg , takes off down a 51.0 m high, 11.0 ∘ slope on his jet-powered skis. The skis have a thrust of 210 N . Sam's speed at the bottom is 41.0 m/s .

asked on October 1, 2015
4. ## Statistics

In a sample of 20 men, the mean height was 178 cm. In a sample of 30 women, the mean height was 164 cm. What was the mean height for both groups put together? The answer I got by adding the two means and dividing them by 2 is 171 but it is wrong, it must

asked on September 20, 2016
5. ## Math/Finance

General Hospital has a current ratio of 0.5. Which of the following actions would improve (increase) this ratio? (Hint: Create a simple balance sheet that has a current ratio of 0.5. Then, judge how the transactions below would affect the balance sheet.)

asked on February 21, 2012
6. ## calculus

The half-life of Radium-223 is 11.43 days. If a sample has a mass of 400 mg, find the mass (in mg) that remains after 6 days

asked on October 14, 2014
7. ## algebra

The length of a spring is a linear function of the mass of the object hanging from it. For a particular spring, the length was 12 centimeters when a 2-kg mass was attached to it. When a 5-kg mass was hung from it, it stretched to a length of 18 cm. Which

asked on June 16, 2013

Which of the following is true of the cause and treatment of ADHD ? A. Drug therapy alone is not very effective in treating hyperactivity b. academic and social skills are best treated with a combination of medication and other treatment. C. Usually caused

asked on October 2, 2015
9. ## chemistry

A compound was found to contain 49.98 g carbon and 10.47 g hydrogen. The molar mass of the compound is 58.12 g/mol. What is the molecular formula?

asked on January 20, 2010
10. ## phisecs

water is moving with a speed of 5 m/s through a pip with a cross-sectional area of 4cm^2 . the water gradual descends 10 m as the pipe cross-sectional area increases 8cm^2 . if the pressure at the upper level is 1.5*10^5 , the pressure at the lower level

asked on April 22, 2014
11. ## Physics

Blood from an animal is placed in a bottle 1.3 m above a 3.6 cm long needle, of inside diameter 0.35 mm , from which it flows at a rate of 2.1 cm3/min . What is the viscosity of this blood? Assume ρblood=1.05×103kg/m3.

asked on March 7, 2017
12. ## science

Describe the change in phase and temperature as water moves from the oceans to the atmosphere and then returns to Earth again as rain. A) evaporation: temperature increases; condensation: temperature decreases; precipitation (rain): temperature decreases.

asked on February 11, 2019
13. ## chemistry

The pain reliever morphine contains 17.900 g C, 1.680 g H, 4.225 g O, and 1.228 g N. What is the emperical formula of morphine?

asked on January 20, 2010
14. ## math

Austin is building a building a rabbit pen with 25 feet of fence. What are the dimensions of the rectangle he should build to have the greatest possible area?

asked on April 11, 2019
15. ## Statistics

I have been working on the following homework problem: Consider Homer and Bart's consumption of potato chips and donuts. Suppose that Marge is in the room 30% of the time that Bart is eating chips and 40% of the time that Bart is eating donuts. Similarly,

asked on April 23, 2015
16. ## Calculus

A block of ice is exposed to heat in such a way that the block maintains a similar shape as it metls. The block of ice is initially 2' wide, 2 'high, and 3' long. If the change in the width of the ice is -1/3 ft/hr, find: the amount of time it will tak

asked on February 7, 2012
17. ## science weather

The hurricane center is MOST likely to be near location ___________ on Monday afternoon. A) I B) II C) III D) IV

asked on February 11, 2019
18. ## Calculus

I am having trouble differentiating x^2 + 2lny = y (solving for dy/dx). I know that I need to do implicit differentiation, but the answer I get is not correct. The answer I got was (2x-2xy)/2, but the answer is (2xy)/(y-2). How do I do this problem?

asked on November 30, 2011
19. ## physics

19. In Figure 10-1, if the force exerted on a 3.0-kg backpack that is initally at rest is 20.0 N and the distance it acts over is 0.25 m, what is the final speed of the backpack?

asked on November 15, 2011
20. ## chemistry

A sample of silver chromate (Ag2CrO4) has a mass of 29.0 g. How many CrO42- ions are present?

asked on January 20, 2010
21. ## M

Small muscle usually occurs before large muscle development think false

asked on November 20, 2014
22. ## Calculus

Find a power series, centered @ x=0, for function f(x)=x/(1+2x). I know this is a maclaurin series, but my work doesn't get the right answer. Can you please show steps? Also,do all power series start with a 1, as in (1+2x+4x^2+...)? Thanks in advance!

asked on March 8, 2012
23. ## chemistry

A compound was found to contain 49.98 g carbon and 10.47 g hydrogen. The molar mass of the compound is 58.12 g/mol. What is the molecular formula?

asked on January 20, 2010
24. ## geometry

a 16 by 18 foot rectangular section will be covered by square tiles that measured 2 feet on each side if the tiles are not cut how many of them will be needed to cover the section of the wall

asked on October 4, 2013
25. ## Calculus

Find a power series, centered @ x=0, for function f(x)=x/(1+2x). I know this is a maclaurin series, but my work doesn't get the right answer. Can you please show steps? Also,do all power series start with a 1, as in (1+2x+4x^2+...)? Thanks in advance!

asked on March 8, 2012
26. ## calculus

How do I integrate x(arctanx) dx? Is it some sort of integration by parts? Can you please show steps? Thanks in advance!

asked on December 15, 2011
27. ## Calculus

If 3x^2-2y^2=4xy + 20, find the point(s) at which the graph from Problem 28 has vertical tangents. I found that dy/dx= (3x-2y)/(2x+2y), but now I don't know what to do. Do I set dy/dx to 0?

asked on December 14, 2011
28. ## phisecs

In a period of 3 h, a man walks 13 km north, turns around and walks 5 km south. Find his average velocity in km/h? Please pay attention to sign. (-) means the average velocity is to the south, (+) means the average velocity is to the North.

asked on February 20, 2014
29. ## Calculus

How do I find the limit of (1+sin(pi times x))^(1/x) as x approaches 0? I tried using wolframalpha, but am unable to understand their steps. My thinking is that you set y=the limit and use L'hopital's rule a couple times. The answer I got was y=e^0--->y=1,

asked on January 19, 2012
30. ## Calculus

The point (1,-2) is on the graph of y^2-x^2+2x=5. Find the value of (dy/dx) and (d^2y/dx^2) at the point (1,-2). How do I find (d^2y/dx^2)? I found. I found (dy/dx) to be 2y(dy/dx)-2x+2=0, but I don't know how to take the derivative of that to

asked on October 18, 2011
31. ## math

two baseball players bat first and second in the lineup the first batter has on base percentage of 0.46 the second batter has an on base percentage of 0.31 if someone is on base but only 0.23 if the bases are empty at the start of the game what is the

asked on January 5, 2011
32. ## chemistry

How many moles are there in 4.76e24 atoms Al?

asked on January 20, 2010
33. ## chemistry

A sample of carbon dioxide has a mass of 47.4 g. How many carbon atoms are present?

asked on January 20, 2010
34. ## physics

Sam and Sue are running side by side in a marathon. They are running at a constant velocity of 10 km h . What is Sue's relative velocity to Sam? A) 0 km/h B) 5 km/h C) 10 km/h D) 20 km/h

asked on October 26, 2016
35. ## Child development

Refers to breaking down complex skills into their component parts? A. Differentiation b. integration c. Motor skills d. Locomotion I am think b but am not sure if it right.

asked on October 2, 2015
36. ## phisecs

`filling the blanks: sun_________________ than moon. earth is__________________mercury.''.

asked on February 21, 2014
37. ## phisecs

In a period of 3 h, a man walks 13 km north, turns around and walks 5 km south. Find his average velocity in km/h? Please pay attention to sign. (-) means the average velocity is to the south, (+) means the average velocity is to the North.

asked on February 21, 2014
38. ## englsih

what is writing conventions and how do i improve min

asked on September 29, 2013
39. ## math

How do I find the length of curve f(x)=3x^2-2x+3 on the interval [1,4]? I have no idea on how to start this. Anyways, thanks in advance!

asked on November 15, 2011
40. ## School

Daily activity can boost academic performance true or false I am think t

asked on November 20, 2014
41. ## phisecs

.: A 5.0 kg block is moving with constant velocity down a rough incline plane. The coefficients of static and kinetic friction between the block and the incline are 0.25 and 0.20, respectively. What is the inclination angle of the incline plane?

asked on March 24, 2014
42. ## phisecs

A car travels in a straight line at 67 km/h for 1 h and at 106 km/h for 2 h. How far does it travel?

asked on February 18, 2014
43. ## geometry

the perimeter of a rectangle is 72. the base is 3 times the height find the area of the rectangle

asked on October 3, 2013
44. ## Math

Let p>q>0 with p+q = 1 and a = q/p < 1. Let X_n denote the random walk with transitions X_{n+1} = CASE 1: X_n + 1 with probability p and CASE 2: X_n - 1 with probability q. For i â‰¥ 0, we set u_i = P(X_n = 0 for some n â‰¥ 0|X_0 = i). Give the

asked on September 7, 2012
45. ## Calculus

Write the first four nonzero terms and the general term of the Taylor serires for f about x=0. f(x)=2x/(1+x^2) I feel that I'm doing this wrong because finding the derivatives of f(x) look really messy. Can you please show me the steps? Thanks in advance!

asked on February 9, 2012
46. ## Calculus

Integrate (1/2)sin(x^(1/2))dx. I've tried using u-substitution, with u=sin(x^(1/2)). du would then = ((1/2)x^(-1/2))(cos(x^(1/2))). As you can see, this only make the problem more complicated. I don't get what to do. Thank you in advance!

asked on January 2, 2012
47. ## Calculus

Integrate dx/xlnx. What method am I supposed to use? I'm totally lost.

asked on January 2, 2012
48. ## Calculus

How do I integrate (e^(3/x))/(x^2) from 1 to 3. I understand how and why I need to do u-substitution, with u=3/x and so dx=(-3 du)/x^2. After plugging (-3 du)/x^2 in for dx, I get a really messy problem that I don't know how to finish. Can you please

asked on November 21, 2011
49. ## Calculus

How do I determine the area of a region bounded by a function and the x-axis if given y=cosx and interval is [0,ð/2]. This has to do with the Fundamental Theorem of Calculus. Thanks in advance!

asked on October 27, 2011
50. ## Euro history

What is the immediate cause of WWII? Is it Germany's invasion of Poland? I can't remember.

asked on April 22, 2011
51. ## Math

I need some help with this question. (5/x-2) = (6/x+6) + {29/(x-2)(x+6)} I don't know how to solve this. Can someone help me figure this out? Thanks.

asked on September 2, 2010
52. ## accounting

The following information is for X Company for 2009: Direct materials purchased \$ 36,484 Direct materials used 34,013 Direct labor 14,439 Overhead 25,464 Work in Process, January 1, 2009 4,118 Finished Goods, January 1, 2009 2,326 Work in Process, December

asked on February 19, 2010
53. ## chemistry

How many moles are there in 23.6g Ag?

asked on January 20, 2010
1. ## Health

W

posted on February 27, 2019
2. ## 5th grade math

e

posted on January 18, 2019
3. ## science(check answers)

1 is false

posted on October 19, 2018
4. ## science(check answers)

Thx for the answers

posted on October 16, 2018
5. ## Science

Help

posted on October 8, 2018
6. ## Physics

Not nice it is not correct answer please check it again

posted on September 2, 2018
7. ## Physics

Not nice

posted on September 2, 2018
8. ## Physics

posted on September 2, 2018
9. ## physics

16.05 N

posted on September 16, 2017
10. ## Science help

desertification

posted on June 16, 2017
11. ## writing english

I think write teacher is a !@#\$%^&

posted on June 15, 2017
12. ## math

♥️ Is correct I got a 5/5

posted on March 28, 2017
13. ## Physics

Decrease to one-ninth

posted on March 7, 2017
14. ## Global Studies

Ann Onymous is right.

posted on January 10, 2017
15. ## ECE

oral

posted on November 28, 2016
16. ## Science

Cotton

posted on May 10, 2016
17. ## Human Sexuality

c

posted on November 29, 2015
18. ## Child Developmental

The second question b or c

posted on October 2, 2015
19. ## Child development

Thanks so for the help.

posted on October 2, 2015

posted on October 2, 2015
21. ## Physics

Wa

posted on September 1, 2015
22. ## statistics

0.0067

posted on May 5, 2015
23. ## School

Small muscle usually occurs before large muscle. I am think false.

posted on November 20, 2014
24. ## phisecs

In a collision, an automobile of mass 826 kg stops with constant acceleration in 20 m from an initial speed of 17 m/s. What is the acceleration of the car in m/s

posted on March 31, 2014
25. ## phisecs

thank you for helping me , but i couldn't find similar question at the bottom or in the search button , could you please give me the link to it . thank you soo much

posted on February 21, 2014
26. ## phisecs

279 thanks

posted on February 18, 2014
27. ## w

does that mean 22 people of every 100 that aplky get accepted

posted on October 2, 2013
28. ## Physics

5A doesn't seem to work

posted on June 17, 2013
29. ## Physics

22.8

posted on June 4, 2013
30. ## Physics

anyone get #6???

posted on May 27, 2013
31. ## Physics

anyone get #6

posted on May 27, 2013
32. ## Physics

anyone????

posted on May 27, 2013
33. ## Physics

anyone get this

posted on May 8, 2013
34. ## Physics

c = 0.00448571428571 d = 0.00897142857143 do you know lightly damped circuit or RC circuit

posted on May 8, 2013
35. ## Physics

heeeelp

posted on May 8, 2013
36. ## Physics

formulas for b and c anyone?

posted on May 8, 2013
37. ## insurance prep

Where i can find information about blocks 18 and 19

posted on July 7, 2012
38. ## 4th grade limericks

So fat and could glow

posted on May 30, 2012
39. ## Calculus

Thank you! That was helpful :)

posted on February 9, 2012
40. ## Calculus

awesome! Thanks Damon ;D

posted on January 2, 2012
41. ## Calculus

very cool. Thanks, both of you! Does wolfram alpha give steps for all integration problems?

posted on January 2, 2012
42. ## Calculus

thanks! that was really helpful ;)

posted on December 14, 2011
43. ## Calculus

Thank you! Now I understand that I should've multiplied by y instead of moving the whole "2/y (dy/dx)" to the other side of the equation and then factor the dy/dx out. I can't believe how such a simple manuever can make the problem so much easier to solve.

posted on November 30, 2011
44. ## Chemistry

change grams to moles using the periodic table then use this equation molarity= moles of solute/liters of solution

posted on April 22, 2011
45. ## algebra

Rewrite the equation to standard form. 6x-5y=15 (6/5)x-y=3 y=(6/5)x-3 The coordinates for y intercept is always in the (0,_) format. Y-intercept is what is added or subtracted. The coefficient on x (number multiplied to x) is slope. slope=6/5

posted on April 22, 2011
46. ## Math

when x=10, y=17 when x=50, y=97 when x=100, y=197

posted on April 22, 2011
47. ## Math

X|Y --- 0|(-3) 1|-1 2|(1) 3|3 4|(5) 5|7 y=2x-3

posted on April 22, 2011