Friday

October 28, 2016
Total # Posts: 267

**Physics trajectory**

A ball rolls off a deck at a speed of 0.7 m/s. The deck is 4.5m above the street. How long does it take for the ball to reach the street?

*October 18, 2016*

**Math**

Let n be any counting number. Using the two questions above as a guide, how many subsets does the set {1,2,3,...,n−1,n} have? Prove it as well. First question:Including itself, how many subsets does the set {1, 2, 3} have? List them. Second Question: Including itself, ...

*September 28, 2016*

**Math**

in a survey, 15 people said they played basketball, hockey and volleyball. in addition 20 people said they played basketball and hockey. draw a venn diagram to determine how many people in the survey said they played only basketball and hockey.

*September 28, 2016*

**Physics**

If it takes 5 seconds for the baseball to fall, how far from the tower will it land? I used vertical distance formula dy=1/2(g)t^2 and got 122.5 but its one of the answers in the multiple choice. Please help.

*September 13, 2016*

**Pre alg**

Simplify: 3x^2+6-2x+5x-4x^2+9 A.-x^2+3x+15 B.7x^2+3x+3 C.x^2-3x+15 D.-x^2+7x+15 I think it's D.

*May 25, 2016*

**pre-calculus**

Rewrite the following expression as an algebraic function of x sin(arccos(x/2)) I know sine is y, which is opposite over hypotenuse. I also know that arccos is the inverse of cosine. I'm confused on what the question is asking and what to do with the x. Please help! Thanks

*April 27, 2016*

**Geometry**

i have no idea

*April 7, 2016*

**Physics**

A block of mass 0.585 kg is placed on the end of a spring which has a stiffness of 294 N/m. It is pulled down 2.80 cm and released. What is the frequency of oscillation?

*April 5, 2016*

**Physics**

A block with a mass of 0.357 kg is attached to a spring of spring constant 599 N/m. It is sitting at equilibrium. You then pull the block down 4.80 cm from equilibrium and let go. What is the amplitude of the oscillation? I know A=D/F... I keep getting the wrong answer though...

*April 5, 2016*

**Chemistry**

At a certain temperature, the reaction has Kc = 5 x 108. If a reaction mixture at equilibrium contains 0.26 M of H2 and 0.087 M of Cl2, what is the concentration of HCl?

*March 26, 2016*

**Physics**

Suppose under the certain conditions, the maximum force of friction that could act on a certain car was 3.35*10^3 N. The mass of the car is 857kg. What is the maximum possible centripetal acceleration of the car going around a bend? I know the equation for this is a=(4piR)/(T^...

*March 22, 2016*

**Physics**

A car is traveling around a bend at a speed of 12.4 m/s. The bend has a radius of curvature of 66.7 m. Friction is the only force acting towards the center of the circle. If the mass of the car is 862 kg, what is the force of friction required to make the car go around the bend?

*March 21, 2016*

**Physics**

A ball is attached to a center post by a string that is 0.382 m long. The ball is moving in a circle on a frictionless table top at a speed of 1.28 m/s with a radius of 0.382 m. What is the centripetal acceleration of the ball?

*March 21, 2016*

**Physics**

If the angular velocity, ω, changes from 7.07 rad/s to 24.2 rad/s over a time of 6.42 s, what is the angular acceleration, α?

*March 21, 2016*

**Physics**

If a wheel turns around 6.00 complete rotations, what would the angular displacement of that wheel be in radians?

*March 21, 2016*

**Physics**

Suppose a 300–g kookaburra (a large kingfisher bird) picks up a 84.0–g snake and raises it 2.30 m from the ground to a branch. How much work did the bird do on the snake? How much work did it do to raise its own center of mass to the branch? I got the first question ...

*March 15, 2016*

**Physics**

Suppose a 300–g kookaburra (a large kingfisher bird) picks up a 84.0–g snake and raises it 2.30 m from the ground to a branch. How much work did the bird do on the snake? How much work did it do to raise its own center of mass to the branch?

*March 15, 2016*

**CALC HELP!**

Find an equation of the tangent line to the graph of y= x+ (4/x) at the point (4,5). I can't figure out the answer to this. It's supposed to be y=3/4x +2 but I can't get that.

*March 9, 2016*

**Science**

So it's D?

*March 3, 2016*

**Science**

1. Which of the following explains why sunlight is important to the aquatic ecosystems? A. Sunlight provides a source of heat and energy to increase water temperatures. B. Sunlight keeps harmful bacteria from taking over aquatic ecosystems. C. Sunlight makes it possible for ...

*March 3, 2016*

**CHEM QUESTION**

In writing and balancing equations using sulfur chemists usually use the empirical formula, S, rather than the molecular formula. Why? I'm not sure how to answer this question.

*March 2, 2016*

**Math!**

I'm sorry I don't really understand... :(

*March 2, 2016*

**Math! **

Describe how you would estimate the square root of a number that is not a perfect square without using a calculator. Can someone please explain? I need some help.

*March 2, 2016*

**Math**

If city AN city BR 175 miles apart on a map the distance between the two towns is 2.5 inches what is the scale of the map

*February 16, 2016*

**CHEM HELP PLEASE**

would it be 1.05E^-8?

*February 3, 2016*

**CHEM HELP PLEASE**

I did a lab where I had to determine avogadro's number. I need to find the uncertainty in number of moles of stearic acid. There were 3 trials and these are the values for the # of moles of stearic acid used for each trial: 4.39E^-7 4.60E^-7 4.50E^-7 I just need help ...

*February 3, 2016*

**Calculus**

Does anyone know how to solve, ln((3x-2)/(x-1))<0

*January 31, 2016*

**Calculus**

Could someone help with this limit problem? lim x-->1 of ((sqrt(6-x))-2)/((sqrt(10-x)-3)) I tried to rationalize the denominator and numerator but it didn't work!

*January 29, 2016*

**Calculus**

Could someone help with this limit problem? lim x-->1 of ((sqrt(6-x))-2)/((sqrt(10-x)-3)) I tried to rationalize the denominator and numerator but it didn't work!

*January 28, 2016*

**math**

A picture is 42 cm by 36 cm. A scale diagram of the picture must fit in a space that is 3 m by 2 m. Write a reasonable scale for the scale diagram.

*January 15, 2016*

**calculus**

Find a cubic polynomial such as f(x)=ax^3+bx^2+cx+d that has horizontal tangents at the points (-5,4) and (4,-4)

*December 19, 2015*

**adv functions urgent**

any math teachers around?

*October 9, 2015*

**Math- simple polynomials**

For 13 it's 1 and 14 a 1/27

*May 21, 2015*

**Math**

Find the area of a triangle on a spherical surface that has a radius of 3cm and angles that measure 75degrees, 160 degrees, and 142 degrees.

*April 29, 2015*

**Math**

Find the length of the side of a right triangle side a is 40 mm the opposite is 41 mm

*April 29, 2015*

**Math**

How much glas is needed to make a fish tank that is 12 inches long, 8 inches wide, and 9 inches high? The tank is open on top.

*April 29, 2015*

**Math**

If 2.7m of ribbon costs $4.99 how much does 0.82m of ribbon cost?

*April 22, 2015*

**Chem **

Pure gold adopts a face-centered cubic crystal structure. It also has a density of 19.30g/mL. What is the edge length of gold's unit cell? What is the atomic radius of gold? I understand how to do this problem the other way: when you have the unit cell and are looking for ...

*April 15, 2015*

**math -ans check**

two points on the graph of a linear function are (-3,5) and (-1,4). Determine the equation of the function in slop-point form. ans: m=-1/2 I pick a point (-1,4) y-y1=m(x-x1) y-4=-1/2(x-(-1)) y-4=-1/2(x+1) Thank you ^^

*March 21, 2015*

**chem**

Calculate glucose levels using standard curve when you have absorbence for sample

*March 15, 2015*

**biochem**

How would I calculate blood glucose levels if using standard curve ...and I have three samples and their absorbence at 420 nm.

*March 15, 2015*

**Physical Science**

Awnser anyone?

*February 7, 2015*

**Math**

Bud and frank were playing a game together and together they scored 56 points. Buds score was 8 times higher than franks what are their scores

*November 18, 2014*

**Math**

Thanks so much!

*November 17, 2014*

**Math**

Heidi has 40 flower arrangemts. Rose arrangements are 4 times as many as tulips how many of each do I have

*November 17, 2014*

**Physics**

Your friend Josh tells you that he spends less on gas in the winter than in the summer. He also says that he has to fill up his tank less often in the winter. (a) Which of the following are possible hypotheses that can be formed from Josh’s observations? (You can choose ...

*November 6, 2014*

**math**

The answer that I got was 22 because 8+10=18 and 18+22= 40

*October 13, 2014*

**Chemistry - Electroplating - URGENT**

Sorry that should say 1115433.526 coulombs, not 8346.453.

*June 17, 2014*

**Chemistry - Electroplating - URGENT**

Ahh thank you - so then there would be 8346.453 coulombs needed instead of 2225.721. As there are two unknowns, I cannot solve this problem any further... this is for an assignment due tomorrow, what should I do?

*June 17, 2014*

**Chemistry - Electroplating - URGENT**

"To save on production costs, most automobile bumpers are never coated with more than 200 g of chromium. Determine how much time a standard bumper should be immersed in a chromium vat." This is what I have so far- 96,485 coulombs are required to plate 1 Cr; 52/6 = 8....

*June 17, 2014*

**math**

there are 30 marbles in a bag; 4 blue, 10 red,6 white, 10 yellow. You randomly draw5 marbles without replacement. Find the percent of drawing 2 red marbles and at least 2 white marbles.

*May 23, 2014*

**English**

What are some good insight questions for A Separate Peace? Some topics can include: Wroter's craft Setting POV

*January 16, 2014*

**algebra 2**

x^2 - 3x + 5 = 0. solve using quadratic formula. show solution

*January 15, 2014*

**GPA**

Currently, my GPA is a 3.5 and I'm a freshman, I'm currently taking two honors classes. Do you think I'll be able to raise it up to a 4.0 by senior year?

*January 15, 2014*

**algebra 1**

The graph models the situation because when you plug in -40 for x, you get y=14, which is a point on the graph. When you substitute 40 in for x, y=10, which is also plotted on the graph.

*November 22, 2013*

**economics**

Suppose the demand curve for a monopolist is QD = 500 − P, and the marginal revenue function is MR = 500 − 2Q. The monopolist has a constant marginal and average total cost of $50 per unit. a.Find the monopolist’s profit-maximizing output and price. ...

*October 17, 2013*

**physics**

Your town is installing a fountain in the main square. If the water is to rise 20 m above the fountain, how much pressure must the water have as it moves slowly toward the nozzle that sprays it up into the air? Assume atmospheric pressure equal to 100,000 Pa.

*October 13, 2013*

**physics **

If you fill a container with air at room temperature (400 K), seal the container, and then heat the container to 500 K, what will the pressure be inside the container? Assume atmospheric pressure equal to 100,000 Pa.

*October 13, 2013*

**Chemistry**

A gas is confined to a cylinder under constant atmospheric pressure, as illustrated in the following figure. When the gas undergoes a particular chemical reaction, it absorbs 827 J of heat from its surroundings and has 0.62 kJ of P−V work done on it by its surroundings.

*October 2, 2013*

**chemistry**

What volume of 0.140 M HCl is needed to neutralize 2.53g of Mg(OH)_2

*September 29, 2013*

**biology**

I need to know how egg whites would react when tested in iodine and Benedict's solution.

*September 22, 2013*

**Government**

Looking for an issue and a solution where the people and the government can help

*September 5, 2013*

**Math**

40% of what is 32?

*August 7, 2013*

**Math**

laura can paint a house in 4 hours and lucky can paint a house in 2 hours. How long would it take for Laura and Lucky to paint a house together?

*August 5, 2013*

**Organic Chemistry**

How do I make an IR Spectrum of C6H12S2 (Allyl Propyl Disulfide)

*April 24, 2013*

**Grammar**

Hi beautiful people! Quick question if you are writing a congratulatory letter should you say - I would like to take the time to congratulate you on your extraordinary commitment to XXX charity. OR - I would like to tak ethe time to congratulate you for your extraordinary ...

*April 11, 2013*

**math**

so I am wrong, thank you for explaining which it can not be. Thanks

*April 2, 2013*

**math**

Which of the following is a formula for finding the volume of a cube? A. v=e^3, where e= the edge length B. v=(lwh)^3, wherel= length,w=width andh=height C.v=6e^2, where e=the edge length D. v=b*b, where b= the area of the base I picked A since V=s^3 or e^3 for the volume of a...

*March 30, 2013*

**maths-linear equation**

(4,3),(-1,6)

*March 11, 2013*

**Calculus**

With is the integral of (9(sinx+cosx))/sin(2x)

*March 7, 2013*

**english**

what would a thesis statement be for Old Jules by Mari Sandoz

*March 4, 2013*

**English I**

Can someone please help me with this analogy? Joints:inflamed::_______atrophy. It is a crossword and there are 7 spaces. Thanks!

*February 5, 2013*

**Chem**

when 2.31 moles of sulfur hexafluoride are synthesized from te elements, how many grams of fluorine were used PLEASEEEEE HELPPPP MEEE!

*February 4, 2013*

**Math**

Given that f(x) = 2x^2 - 8x + 9, 0 ≤ x ≤ 3. (a) Find the average value of f. (b) Find c such that f(average) = f(c).

*January 27, 2013*

**Math**

Find the volume generated if the region bounded by y = sin 2x and y = cos x, π/6 ≤ x ≤ π/2 is revolved about the line y = 2. Use the method of washers.

*January 27, 2013*

**Math**

Find the volume generated. The region is bounded by y = 4x-x^2 and y = 8x-2x^2, and is rotated about x = 2. State which method (washer, disk, cylindrical shell) is used

*January 27, 2013*

**math**

Find the area of the region between the curves y = sin x and y = x^2 - x, 0 ≤ x ≤ 2.

*January 27, 2013*

**pre-algebra**

You split $1500 between two savings accounts. Account A pays annual 5% interest and Account B pays 4% annual interest. After one year,you have earned a total of $69.50 in interest. How much money did you invest in each account?

*January 24, 2013*

**Math**

Find the volume V of the solid obtained by rotating the region bounded by the given curves about the specified line. y = 8 sin x, y = 8 cos x, 0 ≤ x ≤ π/4; about y = −1

*January 24, 2013*

**Math**

The region bounded by the given curves is rotated about the specified axis. Find the volume V of the resulting solid by any method. x = (y − 6)^2, x = 1; about y = 5

*January 24, 2013*

**Math**

Find the volume V of the solid obtained by rotating the region bounded by the given curves about the specified line. y = (64 − x^2)^(1/4), y = 0, x = 6, x = 7; about the x-axis

*January 21, 2013*

**Math**

Find the volume V of the described solid S. The base of S is a circular disk with radius 4r. Parallel cross-sections perpendicular to the base are squares.

*January 21, 2013*

**Math**

The region bounded by the given curves is rotated about the specified axis. Find the volume V of the resulting solid by any method. y = −x^2 + 14x − 45, y = 0; about the x-axis

*January 21, 2013*

**Math**

Translate and simplify "six less than twice the sum Of a number and three. I was not sure how to set it up Is it 2(x+3)-6 Or would it be set up 2x+3-6 I can solve it once I know how to set up the equation. Confused. Thanks for your help

*January 20, 2013*

**Finite Math-Probability**

Suppose we have an urn with 10 white balls and 6 red balls, and we create an experiment by randomly selecting 6 balls from the urn. a) What is the probability that the sample has the same number of white balls as red balls? b) What is the probability that there are more red ...

*November 24, 2012*

**Precal**

Find the exact values of tangent and cosecant for angle theta in standard position whose terminal side passes through the point (16,-4)

*November 4, 2012*

**Math (Calculus)**

I'm pretty sure that you have to either find the angular or linear speed. That's as much as I could tell you. I'm sorry. Could you possibly help me with my question? It's on the current questions page.

*November 4, 2012*

**Pre-Calculus**

An open box is to be made from a piece of cardboard 11 in by 17 in, by cutting out a square of length x from each corner and turning up the sides. Express the volume V of the box as a function of the length x of the side of the square cur from each corner.

*November 1, 2012*

**math**

Thank you for explaining this to us.

*October 17, 2012*

**math**

Hi I am trying to help my 4th grade daughter with homework and I am stuck with this question. Please help and explain how you got the answer. Thanks Jill's fish weighs 8 times as much as her parakeet. Together, the pets weigh 63 ounces together. How much does the fish ...

*October 17, 2012*

**math**

Thank you so much for your help and explaining my wrong answer

*October 14, 2012*

**math**

I make A snack mix by combining 3/4 of a pound of gummy bears with one pound of peanuts. I have 3 1/4 pounds of peanuts a) how many pounds of gummy bears do I need to make the snack mix? b) how many pounds of snack mix can I make? My answers are: I have a) 2 1/2 pounds of ...

*October 14, 2012*

**science**

i have this aswell... we havent learned about it or anything.. it just says, 'explained the big idea of energy' wtf is this

*October 6, 2012*

**Chemistry**

Sulfuric acid, H2SO4, is sold as a 36% aqueous solution. What is this concentration in A. Molality B. Molarity C. The Mole Fraction Please and thank you. :)

*October 1, 2012*

**Chemistry**

21

*September 30, 2012*

**Calc 2**

How to find Cross Section Area given x=5 x=-5 y= sqrt(25-x^2) y= -sqrt(25-x^2)

*September 5, 2012*

**math**

After you have worked out at the gym on a stationary bike for 49.0 minutes, the distance gauge indicates that you have traveled 15.7 miles. What was your rate in km/hr?

*August 27, 2012*

**math**

annie,betty,Cathy and Danial are going to stand on a row for taking pictures. How many ways can they stand?

*August 25, 2012*

**Economics**

Hey I've just had a mind blank. What is the term for when a business has outgrown its limits and is starting to perform badly? Thanks for the help

*August 16, 2012*

**history**

Okay usually on a multichoice test you'd get two questions that are clearly incorrect. Eliminate these. Then look at the remaining two options and choose the "most correct answer". So which one do you think it is?

*August 16, 2012*