Friday

October 28, 2016
Total # Posts: 618

**College Chemistry II**

What is the pH of rainwater at 30C in which atmospheric Co2 has dissolved, producing a constant [H2Co3] of 1.40x10^-5 M? Take into account the auto ionization of water. Im very confused on how to even start this problem

*August 10, 2014*

**College Chemistry II**

What is the solubility of ZnCO3 at 25C in a buffer solution with a pH of 10.21? ZnCO3 <----> Zn++ + CO3 – - CO3-- + H2O ----> HCO3- + OH- pOH = 14 – 10.21 = 3.79 [OH-] = 1.62x10^-4 M = [CO3--] = [Zn++] Ksp = [Zn++][CO3-] = (1.62x10^-4)( 1.62x10^-4) = 2.63x10...

*August 10, 2014*

**Math 221**

Also this goes along with the first question that I asked about Compounded semiannually. P dollars is invested at annual interest rate r for 1 year. If the interest is compounded semiannually, then the polynomial represents the value of the investment after 1 year. Rewrite ...

*August 5, 2014*

**Math 221**

I am trying to figure out how to Evaluate the polynomial resulting from step 1 using: P = $200 and r = 10%, and also with P = $5670 and r = 3.5% am trying to figure out where I start

*August 5, 2014*

**Math**

(v-5)(v+3) Is this answer correct v+15

*August 4, 2014*

**Math 221**

(-4)^-3 is this -12

*August 4, 2014*

**Math 221**

It looks like the first one

*August 4, 2014*

**Math 221**

No the one I wrote is correct you divide by 3x^2 and there was no parentheses

*August 4, 2014*

**Math 221**

24x^5-15x^4/3x^2

*August 4, 2014*

**Math**

7b^3(5b^6+9b) I am trying to see if this answer is correct 35b^9+63b^4

*August 4, 2014*

**Math**

polynomials (4u^2-2u+7)+(-5u^2+u+3)

*August 4, 2014*

**Math**

Thank you :)

*August 4, 2014*

**Math**

I am doing polynomials, is that the same

*August 4, 2014*

**Math**

(-2x^4)^2 y

*August 4, 2014*

**Math 221**

Polynomials x4y5 x3y6

*August 4, 2014*

**psychology**

The success or failure of attempted persuasion can usually be understood by considering the characteristics of the

*July 15, 2014*

** algebra 1**

Evan is making a table that will be created in the shape of the figure below. The table top is a triangle attached to a rectangle. To purchase the right amount of paint, he needs to know the area of the table top. He can only spend $10 on paint, which is enough to cover 150 ...

*July 1, 2014*

**science**

what did u get for the last ones?

*May 8, 2014*

**science**

Its not B its A. I just took this test and I'm looking At the answers. (1 pt) Sequence the same gene in both species to compare their similarity. Incorrect Answer (0 pts) Dissect specimens of both species to look for homologous structures. Unselected answer (0 pts) Search ...

*May 5, 2014*

**math**

The Crabby Apple restaurant lost $2000 in the month of January. If their net worth at the end of the month is -$200. What was the net worth at the beginning of the month?

*May 4, 2014*

**math**

The Crabby Apple restaurant lost $2000 in the month of January. If their net worth at the end of the month is -$200, explain how you would show a child how to find their net worth at the beginning of the month.

*May 4, 2014*

**MATH**

The daily low temperatures during one week were reordered as follows: 2 degrees F, -7 degrees F, 6 degrees F, -3 degrees F, -14 degrees F, -16 degrees F, and -10 degrees F. Explain how you would show a child how to find the average daily low temperature for week.

*May 4, 2014*

**Statistics**

A random sample of 47 students studied for an average of 7.1 hours last week. If the population standard deviation is 1.2 hours, what is the 90% confidence interval for the population mean?

*April 18, 2014*

**Physics**

Henry... where did you get the reference angle from? -72.21??

*March 19, 2014*

**Physics**

a) A bullet (m = 0.0250 kg) is fired with a speed of 91.00 m/s and hits a block (M = 2.80 kg) supported by two light strings as shown, stopping quickly. Find the height to which the block rises. b)Find the angle (in degrees) through which the block rises, if the strings are 0....

*March 12, 2014*

**Physics**

Two children are playing a game in which they try to hit a small box on the floor with a marble fired from a spring-loaded gun that is mounted on a table. The target box is 3.46 m horizontally from the edge of the table. Bobby compresses the spring 0.97 cm, but the center of ...

*March 12, 2014*

**Physics**

Use the following information to calculate the speed of a ball in a pinball machine at a specific location. The ball is launched by using a spring (k = 703 N/m) compressed by 9.0 cm. Consider the starting position of the ball to be its location when the spring is compressed. ...

*March 12, 2014*

**Physics**

True or false Consider a simple frictionless roller-coaster. It begins at x = 0, at a height of y = H. Then it drops into a dip, reaching a minimum at x = 100, with zero height (y = 0). Finally, it goes back up at x = 200, but only reaches a height of y = H/2. Assume the ...

*March 12, 2014*

**life orientation**

Medicine (orthopedic surgery) 1. Numerous opportunities for continued education and connections. 2. Hands on career, always innovating and improving in technological advancements. Writing 1. Have an impact on society through the exploitation of beliefs. 2. Freedom to create ...

*March 12, 2014*

**Physics**

A 3.3 kg pendulum bob hangs from a 2 meter string. It is pulled to the side, position A, so that the bob is 103 cm (h on the sketch) above the lowest position, position C. The bob is released and begins to swing. a) What is its potential energy after it has swung to position B...

*March 12, 2014*

**Physics**

A bead of mass m = 33.5 kg is released from point A which is located 5 m above the ground and slides on a frictionless track. Determine the bead's speed when it reaches point C which is located 2.0 m above the ground.

*March 12, 2014*

**social studies**

Snnsksb

*March 6, 2014*

**algebra 1**

how do you write this polynomial 5x3 + x5 − 8 + 4x in standard form?

*March 5, 2014*

**Chemistry**

Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is the following. Cr2O3(s) + 2 Al(s) → 2 Cr(l) + Al2O3(s) What masses of chromium(III) oxide and aluminum must be ...

*January 21, 2014*

**Latin America/North America**

The alternative for America agreement of the early 2000s is primary aimed to

*December 8, 2013*

**psychology**

How do the experiences of children who feel anxiety or depression compare to those of adults who feel anxiety or depression? Explain your answers.

*December 5, 2013*

**math**

there are 2 times more cats than the number of dogs at a shelter.

*December 2, 2013*

**Math grade 3**

Doug owes75c for overdue library book and $1.10 for another.How much does he owe the library?

*October 26, 2013*

**Math**

Show how to make one addend the next tens number. 26+27=?

*October 23, 2013*

**Math**

It is just an example.

*October 17, 2013*

**Math**

A proton has a size of 1.23x10^-11 and an electron has a size of 1.4x10^-8. How many times smaller is an electron than a proton? Show your work. If I divided 1.23x10^-11 and 1.4x10^-8, wouldn't 1.4x10^-8 be the numerator or the denominator? Please help!

*October 17, 2013*

**Math**

I thought the proton would have to be in the numerator and the electron would be in the denominator for you to divide?

*October 17, 2013*

**Math**

A proton has a size of 0.000000000123 and an electron has a size of 1.4x10^-8. How many times smaller is an electron than a proton? Show your work.

*October 17, 2013*

**Math**

Would I label it cm3 or..? I'm having trouble. :(

*October 11, 2013*

**Math**

For the number of bags I got 9. However I do not know how to label the number 125,664.

*October 11, 2013*

**Math**

Jim wants to plant pansies in his new planter. How much potting soil should Jim buy? Round to the nearest centimeter. Hint: The height is 100 cm and the diameter is 40 cm. My teacher said to use a specific formula. Out of that formula I got 125,664, but I do not know how to ...

*October 11, 2013*

**Math**

Huong covered a box with sticky-backed decorating paper. The paper costs $.03 per square inch. How much money will Huong need to spend on paper if the length is 7 inches, width is 3 inches, and the height is 9 inches? I thought Huong needed to spend $3.42 because I multiplied ...

*October 9, 2013*

**Math**

Huong covered a box with sticky-backed decorating paper. The paper costs $.03 per square inch. How much money will Huong need to spend on paper if the height of the box is 9 inches, width is 3 inches, and the length is 7 inches? Please show full work. Thank you.

*October 9, 2013*

**social studies (history)**

In what ways did the movement of people and technology into and within the Great Plains effect the United States and its residents?

*October 8, 2013*

**physics**

Two soccer players start from rest, 32 m apart. They run directly toward each other, both players accelerating. The first player’s acceleration has a magnitude of 0.55 m/s2. The second player’s acceleration has a magnitude of 0.40 m/s2. (a) How much time passes ...

*October 7, 2013*

**math**

Suppose there are 100 rabbits on an island and that the rabbit population can triple every half-year. Write an equation you could use to find the number of rabbits, R, after t, years. Using your equation, determine the amount of rabbits on the island in year 10. For the ...

*October 1, 2013*

**Physics**

A cyclist maintains a constant velocity of 5.2 m/s headed away from point A. At some initial time, the cyclist is 251 m from point A. What will be his displacement from his starting position after 85 s? Answer in units of m What will be his position from point A after that time?

*September 29, 2013*

**Social Studies (History)**

What are some short-term causes (if any) of the transcontinental railroad?

*September 28, 2013*

**Social Studies**

Oops, sorry wrong one.. That was supposed to be on a different question.

*September 28, 2013*

**Social Studies**

My bad, I haven't read the website carefully enough to see how much materials and tools they need to construct the railroad. I apologize.

*September 28, 2013*

**Social Studies (History)**

1) What are the materials the workers used to construct the first transcontinental railroad? 2) What are the materials in the railroad? 3) What are the long-term and short-term causes of the transcontinental railroad (if there are any short-term causes)? I WILL APPRECIATE YOUR...

*September 28, 2013*

**Social Studies (History)**

The website you provided me was not very informational on the materials.

*September 28, 2013*

**Social Studies (History)**

Were the materials spikes and wood for both Union and Central Pacific railroads to construct the transcontinental railroad?

*September 28, 2013*

**Social Studies (History)**

What were the materials to construct the transcontinental railroad? I already knew the railroad was mostly constructed by hand by thousands of workers, but i need help to find out what kind of materials they used to build and construct the railroad. Also, what are the ...

*September 28, 2013*

**ELA**

how would you use the word generate in a sentence? i'm confused on how to put it in a sentence. I know that generate means cause (something, esp. an emotion or situation) to arise or come about.

*September 27, 2013*

**ela**

what does it mean to: How do those specific word choices and tone contribute to the meaning?

*September 27, 2013*

**english (ELA)**

what is another word for "spill"

*September 27, 2013*

**Math**

(( cube square root of 7)^1/2)^3

*September 19, 2013*

**chemistry**

Polycarbonate plastic has a density of 12 g/cm3. A photo frame is contructed feom two 3 I n sheets of polycarbonate. Each sheet measures 28 cm by 22 cm. What is the mass of the photo frame

*September 3, 2013*

**algebra**

x-6y+32=1 3x-3y+32=-1

*August 25, 2013*

**math**

a student earned a grade of 80% on a math test that had 20 problems. How many problems on this test did the student answer correctly?

*August 10, 2013*

**calculus**

two forces f1 and f2 acting on an object at a 90 degree angle will pull the object with a reluctant force, R, at an angle between f1 and f2. R= ã f1^2+f2^2 R=15 and f1=9 find f2

*July 12, 2013*

**math**

The length of a table is 4m longer than the width. The are is 77m^2. Find the dimensions of the table. l=w+4 w=l-4? I'm stuck?

*July 10, 2013*

**math**

Two cars leave at the same time from towns that are 460 miles apart and travel toward each other. They meet after 4 hours. Find the rate of each car if one car travels 13 miles per hour faster than the other.

*July 5, 2013*

**math**

Kuai, you are awesome!!! Thank you very much! I really appreciate it!

*July 5, 2013*

**math**

An 80% acid solution is to be mixed with a 30% solution to get 90 gallons of a 50% solution. How many gallons of each solution are needed?

*July 5, 2013*

**math**

Thank you, Kuai!!!

*July 5, 2013*

**math**

Wendy invested $6500.00 into two bank accounts, one paying 4% simple interest and the other paying 6%. If her annual interest from the two accounts is $344, how much did she invest at 6%?

*July 5, 2013*

**math**

(x^-3y/x^2)^-3

*July 3, 2013*

**math**

no solution 12 does not = 5

*July 3, 2013*

**math**

x=2 y=-3

*July 3, 2013*

**math**

Much appreciated!!!

*July 3, 2013*

**math**

Let f(x)=9x^2+6x-8, find f(-7)

*July 3, 2013*

**math**

Thank you Steve!

*July 3, 2013*

**math**

f(x)=-7/x-9 What number must be excluded from the domain and why?

*July 3, 2013*

**math**

Thank you Reiny!

*July 3, 2013*

**math**

Ellen wishes to mix candy worth $1.64 per pound with candy worth $3.46 per pound to form 20 pounds of mixture worth $3.00 per pound. How many pounds of the more expensive candy should she use?

*July 3, 2013*

**chemistry**

Determine the gram molecular weight of 3.5 moles of H2O2

*June 27, 2013*

**math**

Any chance you gals would like to go to class with me tomorrow evening? It's 6:00-9:45 pm eastern time in Richmond, IN? Thank you very much for the assistance, I really do appreciate it more than you know.

*June 24, 2013*

**math**

I would love to try that, but I have no idea where to begin. I don't have class until tomorrow night, so I cannot ask my instructor. I am not trying to be selfish with the help I've received from this site. I am grateful and I genuinely need help.

*June 24, 2013*

**math**

And I am very appreciative of the help I've gotten so far. I sincerely am. I am unsure how to set up this problem?

*June 24, 2013*

**math**

Walnuts sell for $10 per pound and pecans for $18 per pound. How much of each type of nut would produce 40 pounds of a mix that sells for $15 per pound?

*June 24, 2013*

**math**

Excellent! Thank you Kuai!

*June 24, 2013*

**math**

Children's tickets to a movie cost $7. Adult tickets cost $12. If 275 tickets were sold for a total of $2490.00, how many of each type were sold?

*June 24, 2013*

**math**

y+3x^2=2 f(x)= f(4)=

*June 24, 2013*

**math**

My bad...

*June 24, 2013*

**math**

Children's tickets to a movie cost $7.00. Adult tickets cost $12.00. If 1275 tickets were sold for a total of $2490.00, how many of each type were sold?

*June 24, 2013*

**math**

Thank you, Sue! That's awesome!

*June 23, 2013*

**math**

The difference between two numbers is 36. The sum of these two numbers is 62. Find the numbers.

*June 23, 2013*

**math**

Thank you Kuai!

*June 23, 2013*

**math**

A 10% acid solution is to be mixed with a 50% solution to get 200 liters of a 20% solution. How many liters of each solution should be used?

*June 23, 2013*

**Algebra**

6x^7-3x^3+2x^7+8x^3=

*June 16, 2013*

**Art**

What about bats, and water? I've seen water in caves.

*June 16, 2013*

**Algebra**

(8x^(2)-4x-29)+(9x^(2)+7x)=

*June 16, 2013*

**eng225**

Satire?

*June 16, 2013*