# Posts by kelly

Total # Posts: 1,739

**physics**

An unmarked police car traveling a constant 95km/h is passed by a speeder traveling 14km/h .Precisely 2.50s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 2.30m/s^2 , how much time passes before the police car ...

*April 15, 2012*

**Science**

The object distance for a convex lens is 15.0 cm, and the image distance is 5.0 cm. The height of the object is 9.0 cm. What is the height of the image?

*April 13, 2012*

**Math**

a.16 inches by 16 inches b.15 inches by 15 inches c.19 inches by 19 inches d.17 inches by 17 inches

*April 12, 2012*

**Math**

Janna is creating a multi-tiered cupcake display for a party. She plans on having 16 cupcakes on each tier. -There is a 1-inch space between all cupcakes. -The cupcakes have a uniform width [diameter] of 3 inches. -Each tier will display the cupcakes in either 2 rows of 8, or ...

*April 12, 2012*

**physics ! HELP PLEASE !!!!1**

what are the methods of computing the veolicty of a particle in one- dimensona motion from a graph ?

*April 10, 2012*

**physcis ! HELP !!!!**

which of collowing situations describe a particle that might have a non-zero velocity? canbe more than one A) a particle that has a constant position as a function of time B) a particle that has its position changing as a fnction of time c)when you graph the particle's ...

*April 10, 2012*

**physics**

which of collowing situations describe a particle that might have a non-zero velocity? canbe more than one A) a particle that has a constant position as a function of time B) a particle that has its position changing as a fnction of time c)when you graph the particle's ...

*April 10, 2012*

**physics**

what are the methods of computing the veolicty of a particle in one- dimensona motion from a graph ?

*April 10, 2012*

**World History**

because

*April 9, 2012*

**algebra**

Using the formula for BMI: B = 703(w)/ h² When the weight is 100 lbs and the BMI is 20, how do I figure out the persons height?

*April 9, 2012*

**physics**

An automobile traveling 95 overtakes a 1.10--long train traveling in the same direction on a track parallel to the road. Q1: If the train's speed is 75 , how long does it take the car to pass it Q2:How far will the car have traveled in this time? Q3:What is the time if the...

*April 8, 2012*

**physics**

An automobile traveling 95 overtakes a 1.10--long train traveling in the same direction on a track parallel to the road. Q1: If the train's speed is 75 , how long does it take the car to pass it Q2:How far will the car have traveled in this time? Q3:What is the time if the...

*April 8, 2012*

**physics**

i got answers to some of the questions Q1: 3.3 mins Q2: ?km <- still need help with Q3:23.3 Q4:?km still need help with

*April 8, 2012*

**physics**

An automobile traveling 95 overtakes a 1.10--long train traveling in the same direction on a track parallel to the road. Q1: If the train's speed is 75 , how long does it take the car to pass it Q2:How far will the car have traveled in this time? Q3:What is the time if the...

*April 8, 2012*

**Science**

Identify 5 different materials that you encounter or use on a daily basis, and identify a mineral that is mined to supply each of those materials.

*April 5, 2012*

**Math**

Thank you for the help :)

*April 3, 2012*

**Math**

The Longhorns punted the ball from the 5-yard line. The punt was caught at the 41-yard line and returned to the 19-yard line. The ball did not cross the 50-yard line. What was the net yardage on the play?

*April 3, 2012*

**Physics Help!!!**

its wrong :/

*April 3, 2012*

**Physics Help!!!**

One of the 79.0 -long strings of an ordinary guitar is tuned to produce the note (frequency 245 ) when vibrating in its fundamental mode. Part A- If the tension in this string is increased by 3.2 , what will be the new fundamental frequency of the string? F= ? Hz i understood ...

*April 3, 2012*

**Physics Help!!!**

One of the 79.0 -long strings of an ordinary guitar is tuned to produce the note (frequency 245 ) when vibrating in its fundamental mode. Part A- If the tension in this string is increased by 3.2 , what will be the new fundamental frequency of the string? F= ? Hz i understood ...

*April 3, 2012*

**physics**

Two point charges are fixed on the y axis: a negative point charge q1 = -23 µC at y1 = +0.23 m and a positive point charge q2 at y2 = +0.33 m. A third point charge q = +7.8 µC is fixed at the origin. The net electrostatic force exerted on the charge q by the other ...

*March 29, 2012*

**math**

A cylinder shaped sculpture is 24 meters high with a diameter of 6.8 meters. An artist plans to spray paint the entire surface with silver paint. If 1 can of spray paint covers 50 square meters, how many cans does the artist need to paint the sculpture?

*March 28, 2012*

**Chemistry III**

I'm sorry thank you so much for all your help but I seem to be getting the wrong answer for part c and I don't understand how to get the individual ion's moles for part b. I have the correct volume of 0.00197L. For part c I am doing as you say and I get a pOH of 5....

*March 27, 2012*

**Chemistry III**

Assume you dissolve 0.240 g of the weak acid benzoic acid, C6H5CO2H, in enough water to make 1.16 102 mL of solution and then titrate the solution with 0.153 M NaOH. C6H5CO2H(aq) + OH -(aq) C6H5CO2-(aq) + H2O(l) (a) What was the pH of the original benzoic acid solution? (b) ...

*March 27, 2012*

**Chemistry II**

You place 1.234 g of solid Ca(OH)2 in 1.00 L of pure water at 25°C and it partially dissolves. The pH of the solution is 12.40. Estimate the Ksp for Ca(OH)2.

*March 27, 2012*

**Chemistry**

A 20.2 mL sample of a weak monoprotic acid, HX, requires 50.0 mL of 0.060 M NaOH to reach the equivalence point. After the addition of 30.0 mL of NaOH, the pH is 5.50. What is the Ka of HX?

*March 27, 2012*

**arithmetic**

The pet shop owner told jean to fill the new fish tank 3/4 full of water.Jean filled the tank 9/12 full.What fraction of the tank does she still need to fill?

*March 21, 2012*

**statistics**

A student is interested in whether students who study with music playing devote as much attention to their studies as do students who study under quiet conditions (he believes that studying under quiet conditions leads to better attention). he randomly assigns participants to ...

*March 18, 2012*

**CHEMISTRY HELP NEEDED!!**

Given info: Reaction: 3A+2B--->2C+D {A] (mol/L) 1.0 ×10^-2 1.0 ×10^−2 2.0 ×10^−2 2.0 ×10^−2 3.0 ×10^−2 [B] (mol/L) 1.0 3.0 3.0 1.0 3.0 Rate of appearance of C (mol/L-hr) 0.30×10^−6 8.10×10^−6 3....

*March 11, 2012*

**Chemistry**

Given info: A] (mol/L) [B] (mol/L) Rate of appearance of C (mol/L-hr) 1.0 ×10^-2 1.0 0.30×10^−6 1.0 ×10^−2 3.0 8.10×10^−6 2.0 ×10^−2 3.0 3.24×10^−5 2.0 ×10^−2 1.0 1.20×10^−6 3.0 ×10...

*March 11, 2012*

**Chemistry**

calculate the specific rate constant between substances A and B has been found to given data 3A + 2B ---> 2C + D

*March 11, 2012*

**Chemistry**

calculate the specific rate constant A] (mol/L) [B] (mol/L) Rate of appearance of C (mol/L-hr) 1.0 ×10^-2 1.0 0.30×10^−6 1.0 ×10^−2 3.0 8.10×10^−6 2.0 ×10^−2 3.0 3.24×10^−5 2.0 ×10^−2 1.0 1.20×...

*March 11, 2012*

**Chemistry**

calculate the specific rate constant A] (mol/L) [B] (mol/L) Rate of appearance of C (mol/L-hr) 1.0 ×10^-2 1.0 0.30×10^−6 1.0 ×10^−2 3.0 8.10×10^−6 2.0 ×10^−2 3.0 3.24×10^−5 2.0 ×10^−2 1.0 1.20×...

*March 11, 2012*

**Chemistry**

collect the specific rate constant....

*March 11, 2012*

**Chemistry**

calculate the specific rate constant A] (mol/L) [B] (mol/L) Rate of appearance of C (mol/L-hr) 1.0 ×10^-2 1.0 0.30×10^−6 1.0 ×10^−2 3.0 8.10×10^−6 2.0 ×10^−2 3.0 3.24×10^−5 2.0 ×10^−2 1.0 1.20×...

*March 11, 2012*

**Chemistry**

calculate the specific rate constant A] (mol/L) [B] (mol/L) Rate of appearance of C (mol/L-hr) 1.0 ×10^-2 1.0 0.30×10^−6 1.0 ×10^−2 3.0 8.10×10^−6 2.0 ×10^−2 3.0 3.24×10^−5 2.0 ×10^−2 1.0 1.20×...

*March 11, 2012*

**Chemistry**

How would you analyze a solution known to contain Hg22+ and Cu2+?

*March 11, 2012*

**PHYSICS**

Determine the value for the acceleration due to gravity at the surface of the planet Mars, given the following data: Mass of Mars = 6 .42 x 10^23 kg Radius of Mars = 3.37 x 10^6 m Thanks!

*March 10, 2012*

**CHEMISTRY**

Ppcl3 6.78 torr Pcl2 26.4 Ppcl5 224

*March 9, 2012*

**Math**

x^2+1/4x+_?__

*March 8, 2012*

**physics**

115.19

*March 7, 2012*

**Physics**

Take the radius of the earth's orbit to be 1.5 x 1011 m. a. Using a year to be 365 days, find the speed of the earth as it moves around the sun. __m/s b. Convert this speed to miles/hour (show your conversion factor in your written backup). __miles/hour

*March 5, 2012*

**Physics**

Take the radius of the earth at the equator to be 6380 km a. Find the speed the speed of an object at the equator due to the earth's rotation. ___m/s b. Convert this speed to miles/hour (show your conversion factor in your written backup). __miles/hour

*March 5, 2012*

**Stats**

Explain how to calculate margin of error. What effect does increasing your sample size have on the margin of error? What effect does it have on the confidence level? What effect does it have on the confidence interval?

*March 1, 2012*

**algebra**

a bag contains only nickels and dimes. there are exactly 18 coins in the bag. the amount of money in the bag is $1.25. let x represent the number of nickels in the bag. let y represent the number of dimes in the bag. 1. write a system of equations that correctly models this ...

*March 1, 2012*

**algebra**

you are planning a cookout. you figure that you will need at least 5 packages of hot dogs and hamburgers in total. a package of hot hods costs $1.90 and a package of hamburgers costs $5.20. you can spend a maximum of $20 in total on the hot dogs and hamburgers. Identify two ...

*March 1, 2012*

**algebra**

find each probability if you pick a card, do not replace it, then pick a second 3 white cards 5 black cards and you pick black, then white

*March 1, 2012*

**Stats**

Explain how to calculate margin of error. What effect does increasing your sample size have on the margin of error? What effect does it have on the confidence level? What effect does it have on the confidence interval?

*February 27, 2012*

**Stats**

Explain how to calculate margin of error. What effect does increasing your sample size have on the margin of error? What effect does it have on the confidence level? What effect does it have on the confidence interval?

*February 26, 2012*

**Math**

1.5x+4y=8 x+y=7 Please help me solve this system of equation and show your work.

*February 25, 2012*

**chemistry**

How many liters of 0.101 m NaCl contains 1.70 mol of this salt? Assume this solvent is H2O. Answer in units of L I do not understand what i am looking for or how to solve for it. Steps would be appreciated.

*February 22, 2012*

**algebra**

A DVD player's laser reader helps to "read" the information on the DVD. A particular laser reader measures 0.56 micron thick. does this fall with the required standards if a company uses |t - 0.03 | <= 0.525 for determining the part to be acceptable?

*February 22, 2012*

**algebra**

A typical DVD can store between 137.9 and 142.1 minutes of data before it is considered full. write an absolute value inequality describing the minutes of data (w) a full DVD will hold.

*February 22, 2012*

**algebra**

A bump on a DVD needs to be between 0.45 and 0.55 micron wide and 0.95 and 0.99 micron high. write two absolute value inequalities describing the width (x) and height (y) of the bump.

*February 22, 2012*

**biology**

suggest a reason for the failure of some of the molecules to diffuse through the semipermeable membrane.

*February 17, 2012*

**Chemistry**

.28C = 30C * x/.2kg x = .001867 moles S .001867 moles S = .48g S/x x = 8.0177 molecular formula for S Is this correct?

*February 17, 2012*

**Chemistry**

If 0.48 g of sulfur are added to 200 g of carbon tetracholoride, and the freezing point of the carbon tetrachloride (Kf=30 degrees C/m) is depressed by 0.28 degrees C, what is the molar mass and molecular formula of the sulfur? .48g * 1mol/32.07g= .01497 mol S .01497/.2 kg = ....

*February 17, 2012*

**Chemistry**

.48g * 1mol/32.07g= .01497 mol S .01497/.2 kg = .07485 molality 273.28K= i * 293K * .07485 i = .08 ??

*February 17, 2012*

**Chemistry**

thank you :)

*February 17, 2012*

**Chemistry**

If 0.48 g of sulfur are added to 200 g of carbon tetracholoride, and the freezing point of the carbon tetrachloride (Kf=30 degrees C/m) is depressed by 0.28 degrees C, what is the molar mass and molecular formula of the sulfur?

*February 17, 2012*

**math**

Assume that you randomly select 8 cards from a deck of 52. What is the probability that all of the cards selected are hearts?

*February 15, 2012*

**Math**

A group of students who are selecting 2 of their group at random to give a report, but assume that there are 5 males and 3 females. What is the probability that 2 females are selected? 2 males?

*February 15, 2012*

**Math**

Assume that you select 2 coins at random from 5 coins: 3 dimes and 2 quarters. What is the probability that all of the coins selected are dimes?

*February 15, 2012*

**sociology**

Social capital refers to the collective value of all "social networks" [who people know] and the inclinations that arise from these networks to do things for each other ["norms of reciprocity"].

*February 14, 2012*

**sociology**

cultural capital is defined as “forms of knowledge, both tangible and intangible, that have value in a given society in relation to status and power Cultural capital defines how people (human) engage each other (social) and their resources (economic).

*February 14, 2012*

**sociology**

what are some examples of social and cultural capital that young children experience

*February 14, 2012*

**Physics**

A 1.7 cm thick bar of soap is floating in water, with 1.1 cm of the bar underwater. Bath oil with a density of 890.0 kg/m3 is added and floats on top of the water. How high on the side of the bar will the oil reach when the soap is floating in only the oil.

*February 9, 2012*

**Physics**

A 1.7 cm thick bar of soap is floating in water, with 1.1 cm of the bar underwater. Bath oil with a density of 890.0 kg/m3 is added and floats on top of the water. How high on the side of the bar will the oil reach when the soap is floating in only the oil.

*February 9, 2012*

**math**

45 1/5 x 3/4 =

*February 6, 2012*

**biology**

the importance of these organic compounds ( carbohydrates, proteinds, lipids) in the cells and tissues of living things

*February 6, 2012*

**Physics**

A ball is thrown upward from the top of a 50.0 m tall building. The ball's initial speed is 12.0 m/s. At the same instant, a person is running on the ground at a distance of 44.0 m from the building. What must be the average speed of the person if he is to catch the ball ...

*February 5, 2012*

**English**

yes i read it but i dnt understand it

*January 31, 2012*

**launguge arts**

I need to un scramble these words and make new ones help eioubdhrs

*January 27, 2012*

**bio101**

2. Find a media piece—article, video, presentation, song, or other—that recognizes the fundamental concepts of chemistry in biology. Include the link or reference citation for the piece and describe how it helped you better understand how fundamental concepts of ...

*January 26, 2012*

**math**

Joe and Bob manufacture bikes. Joe can make 12 bikes in 8 hours while Bob can make 12 bikes in 6 hours. Working together how many hours will it take them to make 12 bikes? Please explain showing steps so I can learn it. I don't just need the answer. Thanks! PS I originally...

*January 26, 2012*

**math**

Joe and Bob manufacture bikes. Joe can make 12 bikes in 8 hours while Bob can make 6 bikes in 12 hours. Working together how many hours will it take them to make 12 bikes? Please explain showing steps so I can learn it. I don't just need the answer. Thanks!

*January 26, 2012*

**physics**

A soccer player kicks the ball toward a goal that is 27.8 m in front of him. The ball leaves his foot at a speed of 18.5 m/s and an angle of 30.4° above the ground. Find the speed of the ball when the goalie catches it in front of the net. (Note: The answer is not 18.5 m/s...

*January 26, 2012*

**algebra**

here's the rest of the info there is angle on one triangle measured 15.5 ft and on another triangle 5ft2 inn and 7ft 9 in

*January 25, 2012*

**algebra**

Jenny is 5ft 2in. tall. To find the height of a light pole, she measured her shadow and the pole shadow What is the height of the pole?

*January 25, 2012*

**biology**

Hydrochloric acid

*January 24, 2012*

**algebra**

determine whether 17 is a solution of the equation 5x+7 = 92

*January 24, 2012*

**chemistry**

Can somone please explain how to do this problem: How many cubic centimeters of olive oil have the same mass as 1.00L of gasoline? the density of gas is .66g/ml and olive oil is .92g/ml Thank you for your help

*January 24, 2012*

**chemistry**

Sorry, it's an 8.0 oz box so there are 16 servings in the box Thanks

*January 24, 2012*

**chemistry**

how many grams of sodium are used to prepare 50 boxes of crackers? sodium per serving is 140mg, serving size is .50 oz for 6 crakers. i got 112g and the answer is suppose to be 110g and i cant figure out how to get 110 thank you

*January 24, 2012*

**chemistry**

why are the atoms in metallic bonds positively charged?

*January 23, 2012*

**physics**

1. Calculate the radius of orbit for a hydrogen electron in the n=3 level. 2.The half life of an unknown substance is one minutes. If the initial number of particles is 20 how many particles will remain after two minutes have elapsed?

*January 23, 2012*

**myths**

what are some modern day myths?

*January 22, 2012*

**Math, Quadratics**

Farmer John is building a pen to keep his pig in. John has 40m of fencing. He will only need to make 3 sides to the pen because the 4th side will be along a barn. If John wants the maximum area what should the side lengths of the pen be?

*January 21, 2012*

**Math, Quadratics**

Hi Damon, I got the same answer as you up to the equation x^2 + 30x - 200=0, but after that I don't understand what happened after that.. where does the 900 and 800 come form? and why you do divide by 2? thanks

*January 21, 2012*

**Math, Quadratics**

Adam has a hockey rink in his backyard. The current dimensions are 10m by 20m. Adam wants to have a hockey tournament and needs to double the area of his hockey rink. How much must Adam increase each dimension if he wants to increase them the same amount?

*January 21, 2012*

**physics**

A rocket is fired at a speed of 75.0 m/s from ground level, at an angle of 59.7° above the horizontal. The rocket is fired toward an 11.0 m high wall, which is located 28.5 m away. The rocket attains its launch speed in a negligibly short period of time, after which its ...

*January 18, 2012*

**Chemistry**

What mass of sodium bromide (NaBr) is required to make 250 cm3 of a 0.35 mol.dm-3 solution?

*January 12, 2012*

**Chemistry**

320g of sulfur dioxide react with 32.0g of oxygen and excess water to form sulfuric acid (H2SO4) a. What is the limiting reagent? b. What is the theoretical yield of product? c. How many grams of excess reagent will remain?

*January 11, 2012*

**Chemistry**

Ethane (C2H6) reacts with oxygen to produce carbon dioxide and water. Assuming there is an excess of oxygen, calculate the mass of CO2 and H2O produced from 1.25 g of ethane

*January 11, 2012*

**7th grade Math**

Sorry Eric, yes I did mean 43 (typo sorry)

*January 11, 2012*

**7th grade Math**

Assume that there are 100 marbles in each bag. Firstly divide 100 by 7 (ratio 4:3) 14.28. Multiply 14.28 by 4 = 57.12 *57 marbles Mulitply 14.28 by 3 = 42.84 *53 marbles Secondly do the same for ratio 3:2 Divide 100 by 5 = 20 Multiply 20 by 3 = 60 marbles Multiply 20 by 2 = 40...

*January 11, 2012*

**fifth grade math**

Daughter has homework problem. P(3,6) is only thing listed. ?

*January 5, 2012*

**math**

Correction...it is supposed to be P(6,3)

*January 5, 2012*

**math**

We don't understand

*January 5, 2012*

**math**

P(3,6)

*January 5, 2012*