Saturday

February 13, 2016
Total # Posts: 2,099

**science**

I took this, and the answers are: 1. B 2. A 3. C 3. C
*April 24, 2014*

**math, calculus**

1. Consider the region bounded by the curves y=|x^2+x-12|, x=-5, and x=5 and the x-axis. A. Set up a sum of integrals, not containing an absolute value symbol, that can be used to find the area of this region. B. Find the area of the region by using your answer from part A. ...
*April 23, 2014*

**Algebra - HELP!!!**

Who knows
*April 22, 2014*

**Probability**

re: E[X^2]: Remember that Var[X] = E[X^2]-(E[X])^2 and also that (in short-hand) Var[X] = E[Var] + Var[E]. Use this last identity to get Var[X]; we already have E[X] so we can easily get E[X^2].
*April 20, 2014*

**Probability**

Because the variance of the sum of two RV's is only equal to the sum of the variances if the two RV's are independent. If the two RV's are dependent then the variance of the sum of the two RV's = sum of the variances + 2*COV(the two RV's)
*April 20, 2014*

**science**

yeah its A
*April 15, 2014*

**Math**

We are learning about proofs. We drew lines between noncollinear points. Our table showed 2 points >> 1 line segment, 3 point >> 3 line segments, 4 points >> 6 line segments, 5 points >> 10 line seg, 6 points >> 15 line seg. etc. Write an ...
*April 12, 2014*

**Physics (Rotation)**

In the figure, wheel A of radius rA is coupled by belt B to wheel C of radius rC. The angular speed of wheel A is increased from rest at a constant rate α. Find the time needed for wheel C to reach angular speed ω assuming the belt does not slip. (Hint: If the belt ...
*April 12, 2014*

**Help Ms.Sue!!! Social Studies**

A B D B B 100%
*April 9, 2014*

**Science/Biology**

Please check my answers: 1. Which of the following correctly states the relationship between monkeys and humans? A. Humans and monkeys evolved from apes. B. Humans evolved from monkeys. C. Humans and monkeys evolved from the same ancestor, which is now extinct. D. Humans ...
*April 4, 2014*

**English**

List as many details as you can for each of the topic sentences. 1. Walking briskly for a mile after a day sitting at a desk helps dispel fatigue. Purpose: To explain 2.Bird watching in the woods is relaxing as well as educational Purpose: To convince
*April 3, 2014*

**Science**

anyone at all?
*April 3, 2014*

**Science**

please help me
*April 3, 2014*

**Science **

fill in the blank questions monotremes, marsupials, and placentals have the same _____ known as the therapsid. a farmer sprays insecticide on his crops and notices that the insect pest problems disappear. a year later he tries the same insecticide only to find that he did not ...
*April 3, 2014*

**social studies(updated answers)**

The answers are CAACD.
*April 3, 2014*

**calculus and vectors**

Determine an equation of the line of intersection of the planes 4x − 3y − z = 1 and 2x + 4y + z = 5.
*April 1, 2014*

**science**

Thanks Amy! THOSE ARE CORRECT.
*March 31, 2014*

**science**

I would like to share my answers for the fill in the blanks. These ARE NOT proven to be correct, but I think most are good and most likely correct answers. Hopefully, you find them helpful. 14. Chemical 15. Heterogenous 16. Density 17. Chem Form 18. Temperature 19. Pressure 20...
*March 31, 2014*

**Math**

Use the following four coordinates to determine which one has a distance of 10 units from point C (1, 2). (3, 4) (7, 1O) (6, 7) (8, 9)
*March 26, 2014*

**American History**

The answer would be D) Harriet Beecher Stowe. He wrote Uncle Tom's Cabin in 1852 before the American Civil War.
*March 26, 2014*

**Economics HELP PLEASE!!!!**

Yes how about this one? Suppose that firms are NOT owned by consumers. Let s denote the size of the per-unit subsidy/tax given to the firms. Let positive values of s denote subsidies, and negative values of s denote taxes. QUESTION: What is the value of s that maximizes total ...
*March 21, 2014*

**AP Calc**

The base of a solid is bounded by y=|x|+a, <a<, and the line y=3. Find, in Cu. units in terms of a, the volume of the solid if every cross section perpendicular to the y-axis is an equilateral triangle.
*March 18, 2014*

**AP Calc**

If x=e^t and y=t^2-3, then for what values of t, t>=0, is the function y=f(x) concave up?
*March 17, 2014*

**AP Calc**

The coordinates of the point on the curve cos(y)=x-y, -pi<=x<=pi, where the tangent line to the curve is a vertical line is ____.
*March 17, 2014*

**AP Calc**

The base of a solid is the region in the first quadrant bounded by the ellipse x^2/a^2 + y^2/b^2 = 1. Each cross-section perpendicular to the x-axis is an isosceles right triangle with the hypotenuse as the base. Find the volume of the solid in terms of a and b. I'm having...
*March 17, 2014*

**AP Calculus**

Approximating the integral from 0 to 6 of (e^x dx) by 3 circumscribed rectangles of equal width on the x-axis yields ____. a) 2e^2 + 4e^4 + 6e^6 b) 2(e^2 + e^4 + e^6) c) 2(e + e^3 + e^5) d) e + 3e^3 + 5e^5 e) e^2 + 3e^4 + 5e^6
*March 17, 2014*

**Math**

idiots
*March 17, 2014*

**AP Calculus**

The average area of all squares with sides between a inches and b inches (b>a) is ____ in^2.
*March 16, 2014*

**AP Calculus**

The base of a solid is bounded by y =|x|+a, 0<a<3, and the line y=3. find in cu. units in terms of a, the volume of the solid if every cross section perpendicular to the y-axis is an equilateral triangle.
*March 16, 2014*

**CALCULUS ECONOMICS**

??
*March 13, 2014*

**Science 6th grade Earth's day and night ANSWERS**

Queen Elsa is right
*March 12, 2014*

**Science 6th grade Earth's day and night ANSWERS**

The answers are correct.
*March 12, 2014*

**science(check answers)**

a d b c
*March 12, 2014*

**science(check answers)**

thanks emily <3
*March 12, 2014*

**science(check answers)**

thanks emily <3
*March 12, 2014*

**science(check answers)**

thanks emily <3
*March 12, 2014*

**science(check answers)**

thanks emily <3
*March 12, 2014*

**science(check answers)**

thanks emily <3
*March 12, 2014*

**science(check answers)**

thanks emily <3
*March 12, 2014*

**science(check answers)**

THANKS EMILY <3
*March 12, 2014*

**science(check answers)**

THANKS EMILY <3
*March 12, 2014*

**science**

An atom of sodium-23 (atomic number = 11) has a positive charge of +1. Given this information, how many electrons does it have? How many protons and neutrons does this atom have?
*March 9, 2014*

**science**

A hydrogen atom has one proton, two neutrons, and no electrons. Is this atom an ion?
*March 9, 2014*

**Probability**

Anyone know answer to 2?
*March 7, 2014*

**Geometry **

In baseball, the length of the path between each pair of consecutive bases is 90 feet. The paths form right angles. How far does the ball need to travel if it is thrown from home plate directly to second base? A. 90 feet B. 127.3 feet C. 135.7 feet D. 180 feet
*March 6, 2014*

**MATH**

I agree with tbetzz
*March 5, 2014*

**MATH**

But why would you subtract the 576 and 144. and plus to find the circumference you were supposed to times the 576 by pi and the 144 by pi
*March 5, 2014*

**Science**

Mariana is right!
*March 5, 2014*

**Physics**

its 54.7 km/s
*March 4, 2014*

**RATIO**

dezz nuts
*March 3, 2014*

**Geometry **

A trapezoid has a perimeter of 14 feet. What will the perimeter be if each side length is increased by a factor 7? A. 21 feet B. 98 feet C. 196 feet D. 686 feet This one is def B correct?
*March 2, 2014*

**Geometry **

A rectangle has an area of 6 square meters. What will be the area of the rectangle if each side length is increased by a factor 5? A. 11 square meters B. 30 square meters C. 125 square meters D. 150 square meters I think the answer is B
*March 2, 2014*

**Geometry**

Is it D?
*March 2, 2014*

**Geometry **

A rectangular prism has a base that is 5 cm by 7 cm and a height of 12 cm. If all dimensions are doubled, what happens to the volume? A. When the dimensions are doubled, the volume is twice the original volume. B. When the dimensions are doubled, the volume is three times the ...
*March 2, 2014*

**Geometry **

A triangle is enlarged by a factor of 3. The perimeter of the new triangle is 36 feet. What could be the lengths of the sides of the original triangle? A. 3 feet, 4 feet, and 5 feet B. 1.5 feet, 1.25 foot, and 1.25 foot C. 2 feet, 0.5 feet, and 1.8 feet D. 4 feet, 4 feet, and ...
*March 2, 2014*

**Geometry **

The circumference of a circle changes from 20 to 4 after a dilation. What was the scale factor of the dilation? A. 1/25 B. 1/5 C. 5 D. 25
*March 2, 2014*

**Geometry **

A circle with a radius of 1/2 ft is dilated by a scale factor of 8. Which statements about the new circle are true? Check all that apply. A.The length of the new radius will be 4 feet. B.The length of the new radius will be 32 feet. C.The new circumference will be 8 times the ...
*March 2, 2014*

**Geometry **

What is the height of a cylinder with a volume of 384π cubic inches and a radius of 8 inches? Round to the nearest tenth of an inch.
*February 28, 2014*

**Geometry **

A cylindrical water tank has a diameter of 20 feet and a height of 15 feet. How much water is needed to fill the tank?
*February 28, 2014*

**math- calculus**

You will often see proj (Vector a onto Vector b) written as projb⃗ a⃗ .Show that projb⃗ a⃗ =(a⃗ ⋅b⃗/ b⃗ ⋅b⃗ )*b⃗ .
*February 26, 2014*

**Physics**

a)5368 N b)5.5 s c)15.24 m d) 2.74 s
*February 24, 2014*

**Science One Question! Help ASAP!!!**

I agree ! ^
*February 24, 2014*

**physics**

(a) A car with a mass of 950 kg is moving to the right with a constant speed of 1.45 m/s. What is the total force on the car? (b) What is the total force on the car if it is moving to the left?
*February 21, 2014*

**math**

A stairway runs up the edge of the pyramid. From bottom to top the stairway is 92 m long. The stairway makes an angle of 70° to the base edge, as shown. A line from the middle of one of the base edges to the top of the pyramid makes an angle of elevation of 52° with ...
*February 20, 2014*

**Black Death**

I have to do a powerpoint on the Black Death. Where can I find the best information to write about it?
*February 19, 2014*

**SCIENCE HELP ASAP! :)**

those answers are wrong, I got 40%. Yayy now I'm failing
*February 19, 2014*

**Geometry**

Is it B?
*February 17, 2014*

**Geometry**

How does the volume of a rectangular prism change if the width is reduced to 1/10 of its original size, the height is reduced to 1/4 of its original size, and the length is reduced to 2/3 of its original size? A. V=1/120lwh B. V=1/60lwh C. V= 2/3lwh D. V=3/4lwh
*February 17, 2014*

**MATH**

David wants to reduce a rectangular image on his computer so that the new image has 25% of the area of the original image. How should David modify the image? Justify your answer.
*February 17, 2014*

**MATH**

Drew has a rectangular postcard that is 6 inches long and 4 inches wide. He uses a photocopier to enlarge it, so that the length and width are 1.5 times as long as those of the original postcard. Explain how the perimeter and area change.
*February 17, 2014*

**Geometry**

Thank you so much oh my god
*February 17, 2014*

**Geometry **

How does the volume of a square pyramid change if the base area is quadrupled and the height is reduced to 1/9 of its original size? A. V= 1/27Bh B. V= 4/27Bh C. V= 2/9Bh D. V= 4/9Bh
*February 17, 2014*

**Geometry**

but that's not a choice. A. 1/6 B. 1/3 C. 3 D. 6
*February 17, 2014*

**Geometry **

The volume of a square pyramid is equal to _____ times the volume of a cube where the bases are the same, but the square pyramid is half the height of the cube.
*February 17, 2014*

**Geometry **

If a cylinder’s radius and height are each shrunk down to a third of the original size, what would be the formula to find the modified surface area?
*February 17, 2014*

**Calc**

Find the coordinates of the point on the curve xy=6 in quadrant I where the normal to the curve passes through the origin.
*February 16, 2014*

**calc**

The slope of the tangent to the curve y=f(x) is given by (1/9)(x^2)(y^2). The curve passes through the point (3,1). Find the value of y when x=3*cubedroot(3).
*February 16, 2014*

**Calc**

it wasn't a typo.. how did you get 10?
*February 15, 2014*

**Calc**

Let f be the function that contains the point (-1,8) and satisfies the differential equation dy/dx=10/(x^2+1) (a) Write the equation of the tangent to f at x=-1. (b) Use your equation in part a to estimate f(0). (c) We know that the integral from -1 to 0 of 10/(x^2+1) equals ...
*February 15, 2014*

**Geometry **

Andrea has a yard shaped like parallelogram ABCD. The garden area, parallelogram EFGB, has an area of 105 ft. If Andrea wants to sod the rest of her yard, how many square feet of sod should she order? A. 765 ft B. 840 ft C. 945 ft D. 1,515 ft
*February 9, 2014*

**Math :-)**

Explain why knowing the height is needed when finding the perimeter of a right triangle.
*February 9, 2014*

**Geometry **

Maria is making a stained glass window in the form of a kite. The width of the window must be 15 in., and she only has enough stained glass to cover 60 in. What should the height of the window be? A. 4 in. B. 6 in. C. 8 in. D. 12 in.
*February 9, 2014*

**Classical mechanics**

Hi juanpro is there other classical mechanic. I might want to join too.
*February 7, 2014*

**Plz, plz help! SS**

Whats that Nicole M??
*February 5, 2014*

**english/writing**

does my thesis statement make sense? is it clear? any suggestions are welcomed In "The Love Song of J Alfred Prufrock," T.S. Eliot used Prufrock to symbolize modern man's fruitless struggle to find self-worth, love, and insecurities of owns appearance. thank you! :D
*February 4, 2014*

**biology**

"ide","ite","ate"
*February 4, 2014*

**Business/ Computers**

Hello I'm doing a powerpoint on the history of computers for business but I just have to look for people. Do you mind giving me a website that would be perfect to find all these people? 1. Blaise Pascal 2. Wilhelm Schickard 3. Christopher Sholes 4. George Stibitz 5. ...
*February 3, 2014*

**math**

I am a math teacher for grade 8 and you are wrong completely off. B C A B A C D C B D C
*February 3, 2014*

**math**

Kat is not right, i got 1/10. here are the correct ones 1) B 2) A 3) C 4) D 5) B 6) D 7) C 8) A 9) A 10) C 11) Essay.
*February 3, 2014*

**math**

I'm confused, is he right or wrong?
*February 3, 2014*

**Science (Chemistry)**

After submitting the answer, this is what I received as feedback. The system is marking that the amount of moles of precipitate was incorrect, although when I did the problem originally I got the same number that you did. I am just posting this feedback for future reference, ...
*February 2, 2014*

**Science (Chemistry)**

A student mixes 35.0 mL of 2.82 M Pb(NO3)2(aq) with 20.0 mL of 0.00221 M Na2C2O4(aq). How many moles of PbC2O4(s) precipitate from the resulting solution? What are the values of [Pb2 ], [C2O42–], [NO3–], and [Na ] after the solution has reached equilibrium at 25 °...
*February 2, 2014*

**Science (Chemistry)**

A student mixes 35.0 mL of 2.82 M Pb(NO3)2(aq) with 20.0 mL of 0.00221 M Na2C2O4(aq). How many moles of PbC2O4(s) precipitate from the resulting solution? What are the values of [Pb2 ], [C2O42–], [NO3–], and [Na ] after the solution has reached equilibrium at 25 °...
*February 2, 2014*

**science**

Write a balanced equation to describe the following reactions: a) C14H30 is cracked to produce ethene, hydrogen and one other compound b) C16H34 is cracked to produce ethene and propene in a 2:1 ratio and only one other compound
*February 1, 2014*

**math**

72 scored higher than 85% 8 scored lower
*January 30, 2014*

**science(check answers)**

Its C lol
*January 29, 2014*

**URGENT Physics PLEASE help**

5. A 1,600 kg car is moving south at 24 m/s. What is its momentum? (Points : 1) 66 kgm/s south 66 kgm/s north 38,000 kgm/s north 38,000 kgm/s south Question 6. 6. The velocity of a 150 kg cart changes from 6.0 m/s to 14.0 m/s. What is the magnitude of the impulse that acted on...
*January 27, 2014*

**Science**

Kiki is right
*January 24, 2014*

**Science**

Planet D. Gravity and Inertia. The Moon would move in a straight line.
*January 24, 2014*

**permutation and combination**

The game of euchre uses only the 9s, 10s, jacks, queens, kings, and aces from a standard deck of cards How many five-card hands have at least two red cards?
*January 23, 2014*