Monday

October 24, 2016
Total # Posts: 3,329

**stat**

Assume that the table below represents the distribution of X. Note that X is a discrete random variable. The second column reports the number of observations for each value of X. Based on this information, what is the variance of X? X n 20 10 25 10 30 5 15 10 10 5

*October 29, 2015*

**Chemistry**

How many oxygen atoms are there in 0.018 mg of H2O?

*October 28, 2015*

**Physics**

A meter stick is rotated about the end labeled 0.00 cm, so that the other end of the stick moves through an arc length of 8.60 cm. Through what arc length s does the 25.0-cm mark on the stick move? I have no clue what Im doing, I know S=tr but what is t?

*October 19, 2015*

**math**

Find the length of a guy wire that makes an angle of 45.5 degrees with the ground if the wire is attached at the top of a tower 63.0 meters high

*October 17, 2015*

**Montwood Middle school **

What is 4/3,-0.09,1.3,85%,-3/8 ordered like in ascending order?

*October 12, 2015*

**Math**

Height of a Projectile. The height of a projectile is described by the equation: s(t)=144t-16t^(2) Where t is in seconds and s(t) is the height of the projectile at time t. Find when the projectile hits the ground.

*October 12, 2015*

**Science **

Hi I've read everything and searched everything and I can't find the answer to this question so... How is iodine-131 and iodine-126 similar and how is it different? Thank you this is stressin me out!

*October 10, 2015*

**help**

The correct answer is D.

*October 9, 2015*

**Statistics**

Do the samples appear to be from the same population? Why or why not? Support your answer with numerical facts and convincing reasons and explanations Chemical distribution stats: Five # summary: (2.29816, 2.29869, 2.299152, 2.30074) Mean: 2.299706 Standard deviation: 0.001313...

*October 8, 2015*

**math**

ok thank you very much for helping

*October 8, 2015*

**math**

ok thanks!

*October 8, 2015*

**math**

So do you multiply 1:8 by 5?

*October 8, 2015*

**math**

scale model is 5 meters

*October 8, 2015*

**math**

if a scale model of a truck is 5m, and the scale is 1:8, what is the length of the truck?

*October 8, 2015*

**Math 125**

how do i solve: a manufacturer of calculators has determined that 10,000 calculators per week will be sold at price of $95 per calculator. At a price of $90, it is estimated that 12,000 calculators will be sold. Predict the number of calculators that will be sold at a price of...

*October 8, 2015*

**physics **

A soccer ball accelerates from rest and rolls 6.5 meters down a hill in 3.1 seconds. It then bumps a tree. What is the speed of the ball right before it hits a tree?

*October 8, 2015*

**Geometry**

The answer is 128 and 52. How did they get the answer?

*October 8, 2015*

**Geometry**

The measure of an angles supplement is 76 less than that the measure of the angles. Find the measure of rhe angle and its supplement?

*October 8, 2015*

**Geometry**

The answer is x=41 and y= 139. How did they get the answe?

*October 8, 2015*

**Geometry**

Set up a system to solve. Two angles are supplementary. Three times one angle is equal to the other angle minus 16. Find the angles. The answer is x= 41 and y= 139. How did they get the answer?

*October 8, 2015*

**Geometry**

The answer is x=20 and y=70 but I don't know how they got the answer..

*October 8, 2015*

**Geometry**

Set up a system to solve. Two angles are complementary. Four times one angle is equal to the other angle plus 10. Find the two angles.

*October 8, 2015*

**Geometry**

The answer is x=48 and y=132 but how did they get this answer?

*October 8, 2015*

**Geometry**

set up a system to solve. Two angles are supplementary. Twice one angle is equal to the other anlge minus 36. Find both angles.

*October 8, 2015*

**AP Statistics**

Do the samples appear to be from the same population? Why or why not? Support your answer with numerical facts and convincing reasons and explanations Chemical distribution stats: Five # summary: (2.29816, 2.29869, 2.299152, 2.30074) Mean: 2.299706 Standard deviation: 0....

*October 7, 2015*

**Physics**

Henry you didn't answer the question

*October 7, 2015*

**Math**

Find the lateral area of a tetrahedron. Slant height is 13in 12in for height.

*October 6, 2015*

**Chemistry**

Thank you so much!!

*October 6, 2015*

**Chemistry**

A sample that is 63.9 % chloride by mass is dissolved in water and treated with an excess of AgNO3. If the mass of the AgCl precipitate is 1.045g, what was the mass of the original sample?

*October 6, 2015*

**Chemistry**

Could someone please walk me through how to solve this problem: A sample that is 63.9 % chloride by mass is dissolved in water and treated with an excess of AgNO3. If the mass of the AgCl precipitate is 1.045g, what was the mass of the original sample?

*October 6, 2015*

**Health**

1: metabolism 2 : fiber 3: protein

*October 5, 2015*

**physics**

a 12uc test charge was placed 20cm from a source of an electric field. There was a measured force of 0.6N acting on the test charge. What is the strength of the electric field measured by the test charge??

*September 28, 2015*

**maths**

If the price of one tin is £t, which of the expressions below represents how much it will cost Morris to buy five tins? 5(t – 1) 5t – 1 t – 5 5t – 5

*September 27, 2015*

**Physics**

You are driving off of a horizontal cliff, again!!! The cliff is measured to be 35.56 m above a rocky ravine floor, but you land 10.36 m away from the sheer cliff face. How fast were you going when you drove off of the cliff?

*September 23, 2015*

**Physics**

You are driving off of a horizontal cliff, and your car has a horizontal velocity of 29.33 m/s at the instant you leave the cliff. The cliff is an unknown height above a rocky ravine, but you land 146.8 m away from the sheer cliff face. How tall is the cliff?

*September 23, 2015*

**Chemistry**

If 2.0 mol of propane are burned (reacted with oxygen), how many moles of carbon dioxide will be produced? C3H8 (g) + 5 O2(g) → 3 CO2 (g) + 4 H2O (g) I just want to make sure the answer is 6 mol of CO2 will be produced.

*September 18, 2015*

**math**

find the product tell which strategy you used (4x10)x10

*September 15, 2015*

**algebra**

You shouldn't call people retarted.. and Damon got the answer right, and you didn't know the answer so maybe you Oscar are "Weird.'

*September 12, 2015*

**algebra**

You shouldn't call people retarted..

*September 12, 2015*

**English**

lmao are those right ^

*September 11, 2015*

**Math**

Evelyn sells used cars he base salary is $800 a week and she receives a 12% commission on each sale represent Evelyn total salary for the week if she had d dollars of sales

*September 10, 2015*

**health**

A patient who lost his or her hearing sometime after birth is said to be A. half-deaf. B. adventitiously deaf. C. incurably deaf. D. congenitally deaf.

*September 9, 2015*

**occupational therapy**

Which of the following questions is best worded for the confused patient? A. "When would you like to go for your walk?" B. "Would you like a drink with your dinner?" C. "What would you like to drink?" D. "When did your illness originate?"

*September 9, 2015*

**Math**

I kinda get it but what is the answer?

*September 2, 2015*

**Statistics**

In advance of the 1936 Presidential Elections, a magazine titled Literary Digest released the results of an opinion poll predicting that the republican candidate Alf Landon would win by a large margin. The magazine send post cards to approximately 10,000,000 prospective voters...

*August 28, 2015*

**Physics**

Consider a cloudless day when the sun shines down across the United States. If 2375 kJ of energy reaches a square meter (m2) of the United States in one hour, how much total solar energy reaches the entire United States per hour? The entire area of the United States is 9,158,...

*August 26, 2015*

**College Physics**

A cyclist is at rest at a traffic light. When the light turns green, he begins accelerating at 2.56 m/s2. How far does he go after the light turns green until he reaches a cruising speed of 10.88 m/s?

*August 25, 2015*

**PLEASE HELP WITH CALCULUS 1 - ITS REALLY URGENT**

ummm could you please be more specific?

*August 21, 2015*

**PLEASE HELP WITH CALCULUS 1 - ITS REALLY URGENT **

Velocities of the 2 cars during the race are given in the tables below where velocities, v are in miles per hour and times t are in seconds. Sappho's car: time: 0 1 2 3 4 5 6 7 8 9 10 velocity:0 20 35 48 62 75 85 93 99 106 111 Homer's car: time: 0 1 2 3 4 5 6 7 8 9 10 ...

*August 21, 2015*

**Calculus - HELP URGENT PLEASE**

yes someone please answer this question

*August 20, 2015*

**Calculus - HELP URGENT PLEASE**

Consider a lake of constant volume 12200 km^3, which at time t contains an amount y(t) tons of pollutant evenly distributed throughout the lake with a concentration y(t)/12200 tons/km^3. assume that fresh water enters the lake at a rate of 67.1 km^3/yr, and that water leaves ...

*August 20, 2015*

**financial management**

Tribke Enterprises collected the following data from its financial reports for 2012: Stock price $18.37 Inventory balance $300,000 Expenses (excluding COGS) $1,120,000 Shares outstanding 290,000 Average issue price of shares $5.00 Gross margin % 40% Interest rate 8% TIE ratio ...

*August 19, 2015*

**computer**

To set up Automatic Backup on your computer, what option would you choose from the Word Options screen?

*August 10, 2015*

**Calculus - HELP URGENT PLEASE**

The region R is bounded by the x-axis, x=2 and y=x^2. Which of these expressions represents the volume of the solid formed by revolving R about the line x=2?

*August 9, 2015*

**Chemestry **

Question 1) Consider the following reaction of calcium hydride (CaH2) with molten sodium metal:CaH2(s) + 2 Na(l) -> 2 NaH(s) + Ca(l) Identify the species being oxidized and the species being reduced? Question 2) Give the names to the binary compounds listed below. Classify ...

*July 27, 2015*

**english**

Whats another way to say "no human rights.." My sentence is starting with "In order to solve.."

*July 17, 2015*

**French SraJMcGin**

My question is.. when i make up these sentences.. how can i make sure that when translated it, it will have the subjonctif

*July 17, 2015*

**Physics**

A 2000 kg car pushes a 3000 kg truck that has a dead battery. The ground pushes forward on the car with a force of 6000 N. What is the magnitude of the force that the truck exerts on the car? Ignore any friction forces. My work/attempts: I've drawn a for body diagram for ...

*July 3, 2015*

**Chemistry**

im very stuck on finding r

*June 29, 2015*

**world history**

Which of these was NOT a shared trait of early Harappan and Mesopotamian civilizations?

*June 24, 2015*

**medical**

It also said that everything else was normal, such as weight and blood pressure

*June 18, 2015*

**medical **

For this assignment, I have to diagnose a list of patients. 1. 14 year old female feels a tightness in her chest when she gets nervous. Also, she starts wheezing when she exercises while being nervous as well as feels a sharp pain in stomach region. I believe this girl has a ...

*June 18, 2015*

**Math (PLEASE HELP!)**

1. Suppose the height, h, in feet, of a trampolinist above the ground during one bounce is modelled by the quadratic function h(t) = -16t2 + 42t + 3.75 . For what period of time is the trampolinist at least 22 ft above the ground? Round your answers to the nearest hundredth. (...

*June 18, 2015*

**physics**

ok i will do that. thanks for the help!

*June 14, 2015*

**physics**

i did delta L = (alpha)(initial L)(delta T) delta L = (12E-6)(58.5)(55.7) = 0.0391 m and i got it wrong. i tried that answer as negative too and it was still wrong. so does anyone know where i went wrong? i REALLY appreciate that help!!!

*June 14, 2015*

**physics**

i wanted to post the exact question so people will have all the information. and i am sorry for making anyone angry. i don't want it done for me, i just want what formulas to use. thanks to anyone/everyone that answers!! :)

*June 14, 2015*

**physics**

A steel section of the Alaskan pipeline had a length of 58.5 m and a temperature of 18.0 °C when it was installed. What is its change in length when the temperature drops to a frigid -37.7 °C?

*June 14, 2015*

**physics**

The brass bar and the aluminum bar in the drawing are each attached to an immovable wall. At 29.0 °C the air gap between the rods is 1.93 x 10-3 m. At what temperature will the gap be closed?

*June 14, 2015*

**physics**

A copper kettle contains water at 29.1 °C. When the water is heated to 86.6 °C, the volume of the kettle expands by 5.56 x 10-5 m3. Determine the volume of the kettle at 29.1 °C.

*June 14, 2015*

**physics**

Ideally, when a thermometer is used to measure the temperature of an object, the temperature of the object itself should not change. However, if a significant amount of heat flows from the object to the thermometer, the temperature will change. A thermometer has a mass of 31.8...

*June 14, 2015*

**physics**

An ice chest at a beach party contains 12 cans of soda at 4.56 °C. Each can of soda has a mass of 0.35 kg and a specific heat capacity of 3800 J/(kg C°). Someone adds a 6.54-kg watermelon at 28.5 °C to the chest. The specific heat capacity of watermelon is nearly ...

*June 14, 2015*

**physics**

Two bars of identical mass are at 29 °C. One is made from glass and the other from another substance. The specific heat capacity of glass is 840 J/(kg · C°). When identical amounts of heat are supplied to each, the glass bar reaches a temperature of 92 °C, ...

*June 14, 2015*

**physics**

How much heat in joules must be added to 0.413 kg of aluminum to change it from a solid at 122 °C to a liquid at 660 °C (its melting point)? The latent heat of fusion for aluminum is 4.0 x 105 J/kg.

*June 14, 2015*

**physics**

A thick, vertical iron pipe has an inner diameter of 0.070 m. A thin aluminum (α = 23x10-6 (C°)-1) disk, heated to a temperature of 89°C, has a diameter that is 4.4x10-5 m greater than the pipe's inner diameter. The disk is laid on top of the open upper end of...

*June 14, 2015*

**STATISTICS**

Find the approximate 84th percentile of the pig pregnancy length distribution

*June 2, 2015*

**chemistry **

Describe the difference in intermolecular forces between the two molecules. How does this affect the properties of the substance first one molecule is made up of H3C,OH,CH3, and another CH3. The second molecule is made up of H3C,O,OH3, and CH3.

*May 29, 2015*

**science (cladogram)**

Oh! and thx San for the response. It help me understand the question better. Thx ;)

*May 28, 2015*

**science (cladogram)**

If the dude was going to pretend to be someone he could have at least spelled Mrs.Sue name right. It is mRs.sue. He clearly forgot the r. It was ov. he was a fake. Trust me, I'm sure Mrs.Sue wouldn't curse a child.

*May 28, 2015*

**physics**

Please help! I want to make sure my answer is correct. Q:A thundercloud has an electric charge of 43.2 C near the top of the cloud and -38.7 near the bottom of the cloud. The magnitude of the electric force between these two charges is 3.95 x 10^6 N. What is the average ...

*May 28, 2015*

**English**

What is the significance of Catherine Earnshaws ghost in Wuthering Heights?

*May 27, 2015*

**math **

Mike has a tree 58ft long and wants to cut it into 24 equal pieces. How long would the pieces be?

*May 26, 2015*

**Art**

I double checked @m1538 and he or she is right. S0 if you are looking to see if it is right it is.

*May 24, 2015*

**geomotry **

In Triangle ABC, AC = BC and mC = 62°. The longest side of the triangle is:

*May 22, 2015*

**French**

Does France have "White House?"

*May 18, 2015*

**algebra**

Alonzo wants to buy a bike for $260. He can pay for it in 8 months if he pays $60 now and $25 each month. If he were to pay $60 now and $20 each month, how many more monthly payments would it take to pay for it?

*May 7, 2015*

**Math **

. At a track meet, 50 people ran the 100-meter dash. 2 people finished in 11 seconds, 5 people finished in 12 seconds, 8 people finished in 13 seconds, 10 people finished in 14 seconds, 21 people finished in 15 seconds, 2 people finished in 16 seconds, and 2 people finished in...

*May 6, 2015*

**Calculus**

h(x) = x+cos(ax) is a family of functions where a is a positive constant such that 0<a<4. Which values of a make h(x) strictly decreasing? Justify your answer. I can't figure this out and help would be appreciated. Thanks in advance!

*May 2, 2015*

**Calculus**

h(x)= x + cos(ax), where a is a positive constant such that 0 < a < 4. For what values of a will h(x) have a relative maximum at x=1? So I found the derivative and got h'(x) = 1- asin(ax). Then I plugged in 1 for x and set the derivative equal to zero, so I have 1 + ...

*May 1, 2015*

**Calculus**

I made a typo. The derivative is 1+ a sin(ax), sorry.

*May 1, 2015*

**Calculus**

h(x)= x + cos(ax), where a is a positive constant such that 0 < a < 4. For what values of a will h(x) have a relative maximum at x=1? So I found the derivative and got h'(x) = 1- asin(ax). Then I plugged in 1 for x and set the derivative equal to zero, so I have 1 - ...

*May 1, 2015*

**Algebra**

The following equation is quadratic. f(x)=(x-7)(3x-2) What are the x-intercepts of the graph of the related equation y=(x-7)(3x+2)? A) -7 and 2/3 B) -7 and 3/2 C) -3/2 and 7 D) -2/3 and 7

*April 30, 2015*

**Calculus**

I'm not sure how to do this; I figured I should use separation of variables but I got the wrong equation. Help is appreciated, thanks! If dy/dx=(1+x)/(xy), x > 0, and y = –4 when x =1, when x =3, y = ? A. 6.433, −6.233 B. 3.898, −3.898 C. 4.711, −...

*April 30, 2015*

**science**

Ok, all of boo's answers are right. believe me. ;)

*April 29, 2015*

**science**

ok, Im going to find out if boo's answers are right...Which I really think is. But for all who are wondering, I will see if right....

*April 29, 2015*

**Calculus-limits**

What is the limit as x approaches a of (sinx-sin a)/(x-a)? a. -sin a b. cos a c. -sin x d. cos x e. undefined Thanks!

*April 29, 2015*

**Calculus-limits**

I'm studying for the AP exam and I can't figure this problem out. I thought the answer was negative infinity but that isn't an option. Thank you in advance! What is the limit as x approaches infinity of (9x-x^2-7x^4)/(x^3+12x)? a. 9 b. 7 c. -7/12 d. -7 e. Does not ...

*April 29, 2015*

**Chemistry**

Sulfur trioxide decomposes into sulfur dioxide and oxygen in an equilibrium. You have a 3.00 L vessel that is charged with 0.755 mol of SO3. At equilibrium, the amount of SO3 is 0.250 mol. 2 SO3 (g) ----> 2 SO2 (g) +O2 (g) A) calculate the equilibrium concentrations of SO2 ...

*April 28, 2015*

**algebra**

The apartment building where Herman lives was built 12 years before his grandmother's house. In 4 years, the apartment building will be twice as many years old as Herman's grandmother's house. How many years ago was Herman's grandmother's house built?

*April 28, 2015*

**Calculus**

Can someone check my work on this problem? I'm studying for the AP test and I would really appreciate any help. Let f(x) = the definite integral from [-2,(x^2-3x)] of e^(t^2) dt At what value of x is f(x) a minimum? a. For no value of x b. 1/2 c. 3/2 d. 2 e. 3 The answer I...

*April 28, 2015*