Friday

May 6, 2016
Total # Posts: 1,846

**Chemistry**

A 10.0 gram sample of a mixture of CH4 and C2H4 reacts with oxygen at 25°C and 1 atm to product carbon dioxide gas and liquid water. If the reaction produces 520 kJ of heat, what is the mass percentage of CH4 in the mixture? PLEASE HELP! I do not know where to even start!
*October 26, 2014*

**Chemistry**

In a titration for the determination of the chloride ion, a solution of 0.1M agno3 is used against a solution, the volume of which is 100ml. At the completion of the titration, the residual concentrations of silver and chloride ions are equal and the total volume is now 125ml...
*October 22, 2014*

**Chemistry**

In a titration for the determination of the chloride ion, a solution of 0.1M agno3 is used against a solution, the volume of which is 100ml. At the completion of the titration, the residual concentrations of silver and chloride ions are equal and the total volume is now 125ml...
*October 22, 2014*

**Physics: mechanics **

A 250g bullet with a speed of 500m/s passes through the center of a 1.5kg square wooden block [ side length 18cm] at rest upon a horizontal frictionless surface. As it exits the block, the bullet has a speed of 150m/s. A) find the initial speed of the center of mass of the ...
*October 20, 2014*

**math**

segment A'B is the image of segment A'B after a translation up by 6 units
*October 16, 2014*

**English (Macbeth)**

Act 3 What information is the audience given about the following characters: Malcolm Macduff Edward the Confessor Siward i really need help i think the answer for macduff is that he is trying to convince malcolm to help him overthrow Macbeth
*October 13, 2014*

**Physics graphing**

Im making a graph of magnetic force vs current, after investigating the magnetic force exerted on a current-carrying wire, and how it varies with current, length, magnetic field and angle. How do I know when to use the point (0,0) on the graph?
*October 13, 2014*

**Biology**

What is the location and effect of waves of contraction in the digestive system.
*October 11, 2014*

**ENGLISH CLASS**

Motivation is poor. complete sentence fragment run-on
*October 9, 2014*

**Biology**

Which heart beat measurement is most indicative of your general health? i think it is your resting heart beat, but im not sure the reason
*October 5, 2014*

**English**

My interpretation is that the moose resembles Christ due to the pain the moose has gone through, similarly to what Christ went through, such as the crown of thorns, and with the moose a girl puts a purple cap on him.
*October 5, 2014*

**alagbra**

5-4(12-3y)=
*September 23, 2014*

**Statistics**

Thats what I chose on my test and they marked it wrong
*September 23, 2014*

**statistics**

A sample of 100 patients who use the drug are followed over time. Those that use the drug have a mean life expectancy of 71.30 years. The mean life expectancy for the general population is 75.62 years. The population standard deviation is 28.
*September 20, 2014*

**statistics**

the wieights of newborn babies are distributed normally, with the mean of approximately 115 oz and a standard deviation of 20 oz. if a newborn baby is selected at random. what is the probability that the baby weighs more than 95 oz?
*September 18, 2014*

**statistics**

the weights of newborn babies are distributed normally, with the mean of approximately 115 oz and a standard deviation of 20 oz. if a newborn baby is selected at random. what is the probability that the baby weighs more than 95 oz?
*September 18, 2014*

**Chemistry**

Consider 2H2 + O2 ¨ H2O. To produce 0.895 g water, how many grams of O2 are required?
*September 15, 2014*

**computer science**

The problem is to calculate the usable area in square feet of a house. Assume that the house has a maximum of four rooms, and that each room is rectangular. I need help writing a program description,analysis,test,and with pseuocode with it.
*September 12, 2014*

**Math**

An all girl college began enrolling boys in 2005. By 2012 the ratio of boys to girls was 3 to 7. If there are 200 more girls than boys how many boys are there?
*September 6, 2014*

**Homework **

Q=wc(T1-T2) find c Can you help me find out how to do this problem PLEASE !! TY
*September 3, 2014*

**algebra**

Factor 24 And 16 6x4 2x8
*September 2, 2014*

**math**

15409
*August 26, 2014*

**math**

to determine the number of trout in a lake, a conservationist catches 111 trout,tags them throws them back into the lake.later 28 throw are caught. 14 of them are tagged. how many trout would be conservationist expect to be in the lake?'
*August 26, 2014*

**Introduction to Psychology**

I am working on a written final project and confused on how to apply psychological theories, processes, and concepts to human behavior. When it a person is believed to be suffering from major depression and then I am to Discuss psychological disorders and treatment approaches ...
*August 16, 2014*

**life science**

Gls bxs kep the fossls safe and permit people to look at al sides
*July 31, 2014*

**stats**

what is the probability that a 6 digit phone number contains at least one 8?
*July 19, 2014*

**math**

1,3,4
*July 15, 2014*

**Physics**

(a) Calculate the linear acceleration of a car, the 0.280 m radius tires of which have an angular acceleration of 15.0 rad/s2. Assume no slippage. (m/s2) (b) How many revolutions do the tires make in 2.50 s if they start from rest? (rev) (c) What is their final angular ...
*June 29, 2014*

**Physics**

Two cars collide at an icy intersection and stick together afterward. The first car has a mass of 1500 kg and was approaching at 9.00 m/s due south. The second car has a mass of 700 kg and was approaching at 15.0 m/s due west. (a) Calculate the final velocity of the cars. (b) ...
*June 26, 2014*

**Statistics**

I'm taking stats online which is making it even more difficult for me and I have nowhere to begin when answering this question. 1. A pharmaceutical industry claimed that their new product will lower the cholesterol level by an average of 14.5. To verify the claim, a ...
*June 22, 2014*

**Physics**

The rocket sled shown in Figure 4.5 accelerates at a rate of 29.0 m/s2. Its passenger has a mass of 66.0 kg. Calculate the direction and magnitude of the total force the seat exerts against his body.
*June 14, 2014*

**Physics**

Howdy Jason, this is Michelle! Unfortunately I tried that, as well as just adding the forces together. Neither are the correct answer. Thanks for trying to help tho :).
*June 14, 2014*

**Physics**

Two teams of nine members each engage in a tug of war. The first team's members have average masses of 67 kg and exert average forces of 1350 N horizontally. The second team's members have average masses of 72 kg and exert average forces of 1361 N horizontally. (a) ...
*June 14, 2014*

**Algebra**

Suppose a cost-benefit model is given by y=2771x/100-x, where y is the cost for removing x percent of a given pollutant. What percent of pollutant can be removed for $36,000? Round your answer to the nearest tenth of a percent?
*June 9, 2014*

**Chem 130**

How does the energy of a principal energy level depend on the value of n? Does a higher value of n mean a higher or lower energy?
*May 13, 2014*

**Chem 130**

How do I do this? Using the symbol of the previous noble gas to indicate the core electrons, write the electron configuration for each of the following elements. (a) zirconium, Z = 40 (b) vanadium, Z = 23
*May 13, 2014*

**Calculus**

Let R be the region enclosed by the graphs y=e^x, y=x^3, and the y axis. A.) find R B.) find the volume of the solid with base on region R and cross section perpendicular to the x axis. The cross sections are triangles with height equal to 3 times the length of their base.
*May 13, 2014*

**Chem 130**

What mass of CO2 could be absorbed by 1.37 g of CaO? What volume would this CO2 occupy at STP?
*May 6, 2014*

**Chem 130**

*Thanks!
*May 5, 2014*

**Chem 130**

Thank!
*May 5, 2014*

**Chem 130**

DrBob222, I still don't understand
*May 5, 2014*

**Chem 130**

Suppose two 100.0 L tanks are to be filled separately with the gases helium and hydrogen. What mass of each gas is needed to produce a pressure of 155 atm in its respective tank at 22°C?
*May 5, 2014*

**Chem 130**

A sample of oxygen gas is collected by displacement of water at 25°C and 1.11 atm total pressure. If the vapor pressure of water is 23.756 mm Hg at 25°C, what is the partial pressure of the oxygen gas in the sample?
*May 5, 2014*

**Chem 130**

If 2.03 g of helium gas occupies a volume of 12.0 L at 22°C, what volume will 6.19 g of helium gas occupy under the same conditions?
*May 5, 2014*

**physics **

one can determine a persons center of mass by having them recline on a plank resting on two scales. A person 2m tall lies on such a plank and the scale near her head reads 405 N and the one near her feet reads 360 N. Find the center of her mass.
*May 2, 2014*

**Physics**

A pirate captain has asked you to help him engineer a new plank to have prisoners walk overboard from. He needs the plan to fall overboard with the prisoners in order not to leave any evidence behind. He has a uniform beam of length 8m and a mass of 100kg is resting on two ...
*May 2, 2014*

**physics**

You lay a board over two wooden pegs. The board has a length of 5m and weighs 25 N. it overhangs the left peg by 1m and the right by 2m. Determine the normal force that each peg exerts on the board.
*May 2, 2014*

**physics **

You are a sucker for scenic overlooks, so you want to build a house overhanging a cliff. The way you do this is by taking a 20,000 N concrete beam and hang it over the edge of the cliff with one edge at the cliff ledge and the other edge 700m away in free space. You plan to ...
*May 2, 2014*

**physics**

A ladder of mass 20kg and length 5m can be held up against a wall because the wall exerts a normal force against it. The grass has a coefficient of a static friction of 0.35. find the normal force of the wall against the ladder.
*May 2, 2014*

**physics**

A turntable with a radius of 12cm is being explored by two bugs, one at 5cm from the center and another, very dizzy beetle at 2cm from the center. The turntable is spinning at 7 rad/s. Which bug will have the greater angular momentum?
*May 2, 2014*

**physics**

You always carry 3 wristwatches. One of them is synchronized with your labs atomic clock. Another is running low on battery and is 3 minutes behind, while the third watch is running 6 minutes fast. All were set to the same time when purchased. List the comparative angular ...
*May 2, 2014*

**Physics**

A figure skater spinning in a circle and dazzling the Olympic judges brings her arms together for a final flourish. 1. Does her angular momentum increase, decrease, or stay the same after she pulls her arm in? 2. Does her angular velocity increase, decrease, or stay the same ...
*May 2, 2014*

**Physics **

A rolling barrel with initial velocity 20 m/s encounters a hill 10m tall to slow it down 1. state where its angular speed is 0 2. state where its rotational kinetic energy will be 0 3. state where its translation kinetic energy will be 0 4. for each of the two flat surfaces ...
*May 2, 2014*

**Physics**

You have a crane boom with a mass of 10000kg being held up by a cable and holding a weight of 2500kg. A. Find the torque caused by the weight B. Find the torque caused by the cable C. Find the torque caused by any other force holding it in equilibrium
*May 2, 2014*

**Physics **

You wonder what would happen if you fired a 9.109e-31kg particle moving at 20 m/s in the x direction of a 1.672e-24kg particle moving at 12 m/s at 110 degrees from the x direction. The lighter particle hits the screen at a 100 degree angle from the x direction. What is the ...
*May 2, 2014*

**Physics**

You shoot your enemy's reflection in the mirror while playing paintball. The y axis is perpendicular to the mirror. The mirror has a mass of 1kg and the paintball has a mass of 0.05 kg. The paintball hits the mirror at a speed of 8 m/s at an angle of 25 degrees from the ...
*May 2, 2014*

**Physics **

Instead of standing in the back of the lane and rolling the ball toward the pins like most people, you place a 5kg bowling ball at rest at the back of the lane and try to hit it toward the pins with a perfectly elastic collision using a 1kg ball rolling at 5 m/s from a 25 ...
*May 2, 2014*

**Physics**

A 25,000kg bowling ball moving at 40 m/s on a path angled at 17 degrees hits a 10000kg bowling ball moving at 25 m/s on a path angled at 60 degrees causing the lighter ball to be deflected of to an 65 degree angle. Assuming this is a two dimensional, perfectly elastic ...
*May 2, 2014*

**Calculus**

Consider the differential equation dy/dx=xy-y. Find d^2y/dx^2 in terms of x and y. Describe the region in the xy plane in which all solutions curves to the differential equation are concave down.
*May 1, 2014*

**Physics **

You have a crane boom with a mass of 10000kg being held up by a cable and holding a weight of 2500kg. 1. Find the torque caused by the weight 2. Find the torque caused by the cable 3. Find the torque caused by any other force holding it in equilibrium
*April 30, 2014*

**Physics**

Your teenage kid finally gets his drivers license. He takes off in your brand new car that weighs 2000kg at 47m/s when he hits a parked semi that weighs 40000kg. They plow forward in a perfectly in elastic fashion in the same direction. What is the velocity of the wreck?
*April 26, 2014*

**Physics**

Your teenage kid finally gets his drivers license. He takes off in your brand new car that weighs 2000kg at 47m/s when he hits a parked semi that weighs 40000kg. They plow forward in a perfectly in elastic fashion in the same direction. What is the velocity of the wreck?
*April 25, 2014*

**Physics **

In one dimension, a 12 kg ball moving to the right at 9 m/s collides with a 4kg ball moving to the left at 3 m/s. The collision is perfectly elastic. Find the final velocities of both balls.
*April 25, 2014*

**Physics**

A 25000kg bowling ball moving at 40 m/s hits a 10000kg bowling ball moving at 25 m/s from behind. It is a perfectly elastic collision, so what are the final velocities of the two balls?
*April 25, 2014*

**Physics **

In one dimension, a 5g ball is moving to the right at 7 m/s collides with an 8g ball moving to the left at 4 m/s for a perfectly elastic collision. What is the final velocity of both balls? I just don't understand the whole left and right thing. I have already worked it ...
*April 25, 2014*

**College Physics**

Can someone check my answers for two and help me with the third? 1) A mass m at the end of a spring of spring constant k is undergoing simple harmonic oscillations with amplitude A. Part (a) At what positive value of displacement x in terms of A is the potential energy 1/9 of ...
*April 25, 2014*

**math**

An item originally cost $16.95 and is on sale or 22%. Find the cost of the item. Explain each step
*April 23, 2014*

**chemistry**

A sample of helium at 20 °C occupies a volume of 3.63 L at a pressure of 3.07 atm. What volume does this helium sample occupy if the pressure is reduced to 2.43 atm while maintaining the temperature at 20 °C?
*April 23, 2014*

**Algebra**

finding the equation to the perpendicular lines. y=x+4; (-7,1)
*April 18, 2014*

**Calc**

Last question! Thanks! Given f(3)=4 and f'(3)=5 find g'(3) where g(x)= 5x/f(x)
*April 17, 2014*

**Calculus**

Given f(3)=4 and f'(3)=5, find g'(3), where g(x)=8x.f(x)
*April 17, 2014*

**physics**

a window easher pushes his brush up a vertical window at constant velocity by applying a force F as shown below. The brush weighs 12 N and the coefficient of the kinetic friction is 0.2. find the magnitude of force F.
*April 17, 2014*

**physics**

Two blocks are connected by a light string that passes over a massless, frictionless pulley as shown. The coefficient of friction between the 4kg block and the surface is 0.4. Find the acceleration of the system and the tension in the string.
*April 17, 2014*

**English**

This is the part I am having trouble with: This led Schultz to leave the shells in random places around her home. She would put them where she was sure to see them and every so often, she picked one up and squeeze it, “grateful for the reminder to live a pinch-me life.&#...
*April 16, 2014*

**English**

My Essay: A Mother’s Sense of Wonder To lose a loved one is very hard to bear, but to lose a parent can be very heart-wrenching for a child at any age. Connie Schultz wrote “My Mom’s Wonderful, ‘Pinch Me’ Life,” which was published in 2012, in the...
*April 16, 2014*

**College Math**

Thank you very much!
*April 16, 2014*

**College Math**

Find the derivative of the following functions: a) f(x)=(3x^2-6 )/(x+2) b) g(x)=sin(e^2 +5x) c) j(x)=6xe^x d) Your velocity is v(t)= t^2 = 1 for 0≤ t ≤ 4. Find or estimate the distance traveled during this time.
*April 16, 2014*

**math**

If I had to divide 680 cm^3/s by 1.767 cm^2 and needed an answer in m/s..how would I do that? Just cancel out two cm's and then divide by 0.01?
*April 15, 2014*

**College Physics**

A uniform stationary ladder of length= 5.1 m and mass= 15 kg leans against a smooth vertical wall, while its bottom legs rest on a rough horizontal floor. The coefficient of static friction between floor and ladder is μ = 0.41. The ladder makes an angle θ = 51° ...
*April 11, 2014*

**Physics **

A cannon launches a ball with the initial speed of 210 m/s at a 70 degree angle. 1. How high will the cannonball go? 2. If the cannonball has a mass of 25kg how much work does it take to launch the cannonball to that height?
*April 11, 2014*

**Physics**

Standing at the edge of a cliff 240 m tall. You throw a ball into the air one directly upward at 5 m/a and another downward at -5 m/s. Use conservation energy to show that they will have the same speed at the bottom. I know I have to do it twice.. And it should seem simple. I...
*April 11, 2014*

**physics help!**

A uniform stationary ladder of length= 5.1 m and mass= 15 kg leans against a smooth vertical wall, while its bottom legs rest on a rough horizontal floor. The coefficient of static friction between floor and ladder is μ = 0.41. The ladder makes an angle θ = 51° ...
*April 10, 2014*

**Physics**

I think I got it. c) ω0 t + (0.5*α*t^2) d) 911.3 Can you just double check this?
*April 2, 2014*

**Physics**

I already figured out the answers to some but I need help with two more. 1) A disk with an initial angular velocity ω0 = 4.5 rad/s experiences a constant angular acceleration of α = 7.5 rad/s2 for time t = 15 s. Please answer the following questions. ω0 = 4.5 ...
*April 2, 2014*

**Physics**

Thanks for taking a look! A baseball of mass m1 = 0.46 kg is thrown at a concrete block m2 = 8.25 kg. The block has a coefficient of static friction of μs = 0.81 between it and the floor. The ball is in contact with the block for t = 0.165 s while it collides elastically...
*March 25, 2014*

**Math**

One of my questions say 16, base 4. It says to write it as an exponent but which one is which?
*March 19, 2014*

**Physics**

(Need Help Only For Last Question! I figured out the first two.) A car of mass m = 1130 kg is traveling down a θ = 11 degree incline. When the car's speed is v0 = 11 m/s, a mechanical failure causes all four of its brakes to lock. The coefficient of kinetic friction ...
*March 18, 2014*

**math**

If a store owner buys a microwave for $200 and sells it for $275. What is the percent markup based on cost?
*March 15, 2014*

**English**

Thanks... And Post in the same name? If your referring my husbands posting yesterday that he used my account. I apologizes for that. It wasn't me. Thanks again for the help. And it does help. Have a great day!!!
*March 14, 2014*

**English**

Yes you did which I am extremely grateful. :) But now I need to make it longer and into two paragraphs. I am drawing a blank as to what to add to complete the task.
*March 14, 2014*

**English**

I need to make this into two paragraphs and make it a little longer. I am drawing a blank. Can someone please help me. My study habits consist of reading aloud, note taking and last minute cramming. The reading aloud and note taking have always worked well for me. Last minute ...
*March 14, 2014*

**Physics**

A traffic light is hanging from two cables tilted at 37 and 42 degrees. If it has a mass of 2.3 kg find the tension in each cable.
*March 14, 2014*

**Physics**

A freight train has a mass of 4.78 * 10^7 kg. the locomotive provides a force of 1.3 * 10^6 N and the brakes provide a force of -3.2 * 10^3 N. 1. How long will it take for the train to accelerate to it's maximum speed of 15 m/s? 2. The train accidentally stumbles into an ...
*March 14, 2014*

**English**

Can someone help me figure out what me figure out what my teacher is talking about here. I had to write a self introduction and she told me that I had spelling errors and redundant words. I don't see where she's talking about. My name is Devyn Donahue. I am originally ...
*March 13, 2014*

**English**

Got it!! Thank you so much for your help.
*March 13, 2014*

**English**

Does this sound any better? My study habits consist of reading aloud, note taking and last minute cramming. The reading aloud and note taking has always worked well for me. Last minute cramming hasn’t work very well. I seem to always draw a blank on test day. I found ...
*March 13, 2014*

**English**

Hi, Can someone help me with my online Psychology assignment? She is a stickler for punctuation and grammar. I have not taken English yet. I need all the help I can get. The following is my assignment and response. For this assignment, I'd like you to think about your ...
*March 13, 2014*

**math**

Help pleaseeee The Hotel Regal has 500 rooms. Currently the hotel is filled. The daily rental is $ 400 per room. For every $4 increase in rent the demand for rooms decreases by 8 rooms. Let x be the number of rooms that are being rented in the hotel. What should x be so as to ...
*March 5, 2014*

**Science**

Umm may I ask Daniel Brown if you are in Commonwealth Connection Academy?
*March 4, 2014*

**Science**

I am not sure because I am trying to check the same quiz :(((
*March 4, 2014*