Monday

May 25, 2015

May 25, 2015

Total # Posts: 637

**probability**

E[T]=9
*May 16, 2015*

**chemistry**

under what conditions could the decomposition of Ag2O(s) into Ag(s) and O2(g) proceed spontaneously at 298 K? 2Ag2O(s)---->4Ag(s)+O2(g) dG=22.42 Kj answer= 0.000118 atm.
*May 9, 2015*

**chemistry**

dG for the formation of Hi(g) from its gaseous elements is -20.2 kj/mol at 500k. when the partial pressure of HI is 10 atm, and I2 0.001 atm, what must the partial pressure of hydrogen be at this temperature to reduce the magnitude of dG for the reaction to 0. H2(g)+I2(g)----&...
*May 9, 2015*

**college chemistry**

at its melting point, O c, the enthalpy of fusion of water is 1.435 kcal/mol. what is the molar entropy change for the melting ice at 0C? answer: 5.26 cal/mol-k
*May 9, 2015*

**college chemistry**

thanks
*May 9, 2015*

**college chemistry**

for the reaction at 298 K 2A+b ---->C enthalpy=100 K/cal entropy= 0.050 kcal/k assuming enthalpy and entropy to be constant over the temperature range, at what temperature will the reaction become spontaneous? answer: T>2000K
*May 9, 2015*

**college chemistry**

im confused i found those as the standard enthalpies and entropies for pcl3? i cant get answer
*May 9, 2015*

**college chemistry**

is it 306.4/33.2?
*May 9, 2015*

**college chemistry**

what is dHvap?
*May 9, 2015*

**college chemistry**

estimate the normal boiling point of Pcl3 answer: 333 K how do you get it?
*May 9, 2015*

**Chemistry**

Check my work & answer please. I need to make sure I am able to do this type of problem correctly. A typical car engine produces 44,000 kJ of heat in an hour. The cooling system has a capacity of 8.40 L and is filled with a 50:50 mixture of anti-freeze (specific heat capacity ...
*April 19, 2015*

**Chemistry**

4. A typical car engine produces 44,000 kJ of heat in an hour. The cooling system has a capacity of 8.40 L and is filled with a 50:50 mixture of anti-freeze (specific heat capacity of 8.37 J/g-oC, density of 1.038 g/mL). In maintaining a constant engine temperature, the ...
*April 18, 2015*

**Physics**

A 1100- kg car collides with a 1400- kg car that was initially at rest at the origin of an x-y coordinate system. After the collision, the lighter car moves at 20.0 km/h in a direction of 25 o with respect to the positive x axis. The heavier car moves at 23 km/h at -50 o with ...
*April 16, 2015*

**Earth Science**

You doing this? pkwy.k12.mo.us/homepage/skang/file/Astronomy%20Review.pdf From here the answer would be C - Full moon.
*April 9, 2015*

**Math**

Volume of cube = 1ml How many ml in 1.5L?
*April 9, 2015*

**science**

Compare today's temperature of the universe to the temperature of the universe right after the big bang. That will give you your answer.
*April 9, 2015*

**science**

The average temperature of the universe today is approximately 2.73 kelvins (−270.42 °C; −454.76 °F), based on measurements of cosmic microwave background radiation. What was it like back then?
*April 9, 2015*

**science**

I'm sorry but please reread the article. We even quoted the answers for you but you don't want to put any effort into reading them and trying to figure out what the quotes are saying. You want the answer to be handed you.
*April 9, 2015*

**science**

Thank you Ms. Sue
*April 9, 2015*

**science**

2 - 3 paragraphs down it says... "For the first 380,000 years or so, the universe was essentially too hot for light to shine, according to France's National Center of Space Research " Miss that too?
*April 9, 2015*

**science**

You obvously didn't read it. The very first sentence in that post the Ms. Sue posted is "The universe was born with the Big Bang as an unimaginably hot, dense point." ... how did you miss that??
*April 9, 2015*

**math**

As Ms. Sue mentioned you posting under many names today. Instead of asking questions, why not try to help others or even at least do some work on your questions instead of guessing. I don't mean to be rude here.
*April 9, 2015*

**math**

Wrong. Its B The office building is designed with n floors and each floor is 3.9m right so you have right now: 3.9n On top of entire office building is a antenna which is 15.85m tall so its 3.9n + 15.85 = h
*April 9, 2015*

**Math**

Yes, your answer is A as mentioned by Steve
*April 9, 2015*

**Calculus**

Thank you so much!
*April 9, 2015*

**Calculus**

Suppose that y=f(x) = sqrt(2x), x>=0 Find a c > 0 such that the tangent line to the curve y = f(x) at x = c has the same slope as the tangent line to the curve y = f^–1(x) at x = c. You get: c = 1/8 c = 1/2 c = (1/8)^(1/3) c = (1/3)^(2/3) c = (1/2)^(1/3)
*April 9, 2015*

**math**

coin = 1/2 Cube has number 1, 2, 3, 4, 5, and 6 so 2, 4, 6 are even numbers which is 1/2 of the cube So 1/2*1/2 = 1/4
*April 9, 2015*

**Calc AB**

Thank you. I was taking the inverse of (x+3)^3 + 2 and then I got stuck after that.
*April 9, 2015*

**Calc AB**

Let f(x) = (x+3)^3 + 2. The graph of the inverse function y = f^–1(x) has a vertical tangent at: (Hint: Think about the symmetry of the 2 graphs.) (66, 1) (2, –3) (10, –1) (–3, 2) (–1, 10)
*April 9, 2015*

**Math**

Got this one. Its 1/24 correct?
*April 9, 2015*

**Math**

Suppose f(x) = 4x^5-(1/x^4) Find the slope of the tangent line to the graph of y = f^–1(x) at (3, 1). You get: 1/24 1/16 00062 1620 972
*April 9, 2015*

**Calc AB**

Are you possibly Steve Hawkins? Your getting this one after another.
*April 9, 2015*

**Calc AB**

Suppose that f(x) is an invertible function (that is, has an inverse function), and that the slope of the tangent line to the curve y = f(x) at the point (2, –4) is –0.2. Then: (Points : 1) A) The slope of the tangent line to the curve y = f –1(x) at the point...
*April 9, 2015*

**Math**

It was B
*April 9, 2015*

**Math**

B??
*April 9, 2015*

**Math**

derivative: sin(pi*cosx) = -pi sin(x) cos(pi cos(x))
*April 9, 2015*

**Math**

Inverse of sin(pi*cosx) = cos^(-1)((sin^(-1)(x))/pi) Derivative of cos^(-1)((sin^(-1)(x))/pi) is -1/(sqrt(1-x^2) sqrt(pi^2-sin^(-1)(x)^2))
*April 9, 2015*

**Math**

Suppose f(x) = sin(pi*cosx) On any interval where the inverse function y = f –1(x) exists, the derivative of f –1(x) with respect to x is: a)-1/(cos(pi*cosx)), where x and y are related by the equation (satisfy the equation) x=sin(pi*cosy) b)-1/(pi*sinx*(cos(pi*cosx...
*April 9, 2015*

**Calc AB**

c)(1/2)x^(-1/2) is the correct answer
*April 9, 2015*

**Calc AB**

Wait f^-1(x) is 2sqrt(x) so then the derivative of that is 1/sqrt(x)
*April 9, 2015*

**Calc AB**

That would be 1/(dy/dx) of x^2-4x+4 which would be 1/2x-4 correct?
*April 9, 2015*

**Calc AB**

Suppose that y = f(x) = x^2-4x+4 Then on any interval where the inverse function y = f^–1(x) exists, the derivative of y = f^–1(x) with respect to x is: a) 1/(2x-4) b) 1/(2y-4), where x and y satisfy the equation y=x^2-4x+4 c)(1/2)x^(-1/2) d)(1/2)x^(1/2) e) Both 1/(...
*April 9, 2015*

**Calculus AB**

Yep I was correct
*April 9, 2015*

**Calculus AB**

well lets see. Since f^-1(x) = 9-x^2 then the derivative of 9-x^2 is -2x correct?
*April 9, 2015*

**Calculus AB**

For the function f(x) = sqrt(9-x), which is equal to d/dx(f-1( -1 is the inverse)(x)) a) -2x b) sqrt(x) + 9 c) x^2 + 9 d) 2x e) 9-x^2
*April 9, 2015*

**Calculus**

Answer is 1/(2y-4) where x and y are related by the equation (satisfy the equation) x=y^2-4y+5 x>= 1
*April 9, 2015*

**Calculus**

inverse of x^2 - 4x +5 is 2±sqrt(x-1) and the derivative of that is (2x-4) but I don't know how to get the x>= 1 or x>= 2
*April 9, 2015*

**Calculus**

For the function f(x) = x^2 - 4x +5, x>= 2, which is equal to d/dx (f-1 this is the inverse)(x)) ? 1/(2y-4) where x and y are related by the equation (satisfy the equation) x=y^2-4y+5 x>= 1 2y-4 where x and y are related by the equation y= = x^2 - 4x +5, x>= 2 1/2x-4 ...
*April 9, 2015*

**Calc AB**

I believe that it is Either I or III
*April 9, 2015*

**Calc AB**

Remember that f(x) must be one-to-one (only one y-value for each x-value) over the domain where f –1(x)is defined as a function. So, in some cases you must restrict the domain of f(x) so that it's one-to-one. There might be more than one section of domain that's ...
*April 9, 2015*

**Calc**

Figured it out. 33/2
*April 9, 2015*

**Calc**

Find the area of the region bounded by the curves y2 = x, y – 4 = x, y = –2, and y = 1. So far I have found that the area of the trapezoid which is 13.5. But for the other two areas I cannot find them. They could be: 27/2 22/3 33/2 34/3 14 I believe that it is 14 as ...
*April 9, 2015*

**Physics**

A rock is thrown directly upward from the edge of the roof of a building that is 35.3 meters tall. The rock misses the building on its way down, and is observed to strike the ground 4.00 seconds after being thrown. Neglect any effects of air resistance. With what speed was the...
*March 21, 2015*

**science**

Measuring the speed of light thru gelatin using a laser
*March 4, 2015*

**algebra**

Use the formula d = 1.22ãx to estimate how many miles a 5-foot-tall person can see standing on the deck of a ship that is 50 feet above the ocean.
*February 9, 2015*

**Physics**

A gardener pushes a mower at a distance of 900 m while mowing the yard. The handle of the mower makes an angle of 40.0 with the ground. The gardener exerts a force of 35.0 n along the handle of the mower. How much work does the gardener do in mowing the lawn?
*January 26, 2015*

**Science**

no its alleles
*November 6, 2014*

**science**

Hey thanks.
*November 6, 2014*

**science**

is a starch a complex carboydrate
*November 6, 2014*

**science**

is a complex sugar an example of a starch? is a simple sugar an example of glucose?
*November 6, 2014*

**science**

are starches and glucose all types of carbohydrates?
*November 6, 2014*

**Math**

Find the coordinates of the point at 180 degrees on a circle of radius 3.4 centered at the origin. Round your answers to three decimal places, if required. ( , 0 ) I got 0 as the y coordinate. Please help me solve for x
*October 24, 2014*

**math**

A craft store bought paint for a wholesale price of 100 the store charges a 65% markup what is the craft stores price for the paint.
*October 21, 2014*

**math**

From a box containing 5 blue marbles,10 red marbles,and 8 yellow marbles,Lisa removed 3 marble,one of which was blue.f she removes one more marble at random,what is the probability that it will be blur? a. 1/4 b. 5/21 c. 1/5 d. 2/7 e. 1/6 please answer and explain
*October 16, 2014*

**maths**

95. Suppose that 387 people will travel on a space shuttle with room for 420 people.Each compartment seats 14 people before the next compartment opens.How many people will ride in the last compartment that opened?
*October 9, 2014*

**maths**

99. From a box containing 5 black marbles,8 pink marbles, 6 white marbles, and 5 yellow marbles, Kim removed 4 marbles,one of which was black.If she removes one more marble at random,what is the probability that it will be black? a. 1/6 b. 4/21 c. 1/5 d. 5/21 e. 1/4 please ...
*October 9, 2014*

**english 122**

when you contribute to a research conversation, which of the following skills is not strictly?
*October 9, 2014*

**Physics**

Two small charges with a mass of 1.0 g each are connected by 2.0-cm-long insulating rod of negligible mass. Each ball has the same magnitude of charge of 10 nC, but with opposite sign. The rod is held in a 1.0 × 104 N/C uniform electric field at the angle of 30°, ...
*October 8, 2014*

**algebra**

When reading some schematics of a rectangular garden you see the binomial x +8 feet represents the length and the binomial x - 1 represents the width. Write an expression that represents the total area of the garden in the form x2 (squared) + bx + c by using the distributive ...
*September 18, 2014*

**math**

Linda did 24 problems out of 25 correctly.In the next test she did twice as many examples correctly but received a mark only half as good.How many problems were there in the second test?
*September 18, 2014*

**math**

Age Group (Per cent) 46 and over (25) 40-45 (34.5) 35-39 (25.62) 30-34 (12.9) Under 30 (1.9)
*September 18, 2014*

**math**

Distribution of Employees in National Insurance Company by age groups:(for questions 76-78) Age Group Per cent 46 and over 25 40-45 34.5 35-39 25.62 30-34 12.9 Under 30 1.9 76. Thirty thousand employees of this company are 46 years or over.How many thousand(to the nearest 0.1 ...
*September 18, 2014*

**trigo**

An airplane travels on a bearing of 245 degrees at an airspeed of 200 kilometers per hour while a wind is blowing 50 kilometers per hour from 140 degrees. Find the ground speed of the airplane and the direction of its track, or course, over the ground.
*September 16, 2014*

**math**

A point,X ,is 25 feet from the center of a circle.If the diameter of the circle is 14 feet,what is the length (in feet)of a tangent from point X to the circle? a. square root 29 b. 18 c. 15 square root 2 d. 24 e. square root 673 please answer and explain
*September 14, 2014*

**statistics**

Advertisers contract with Internet service providers and search engines to place ads on websites. They pay a fee based on the number of potential customers who click on their ad. Unfortunately, click fraud—the practice of someone clicking on an ad solely for the purpose ...
*August 11, 2014*

**physics**

Two boat landings are 8.0 km apart on the same bank of a stream that flows at 2.8 km/h. A motorboat makes the round trip between the two landings in 50 minutes. What is the speed of the boat relative to the water?
*August 10, 2014*

**math**

What is the value of 4^5 + 4^5 + 4^5 + 4^5 + 4^5 + 4^5 + 4^5 + 4^5 + 4^5 + 4^5 + 4^5 + 4^5 ? a. 12 x 2^5 b. 24^5 c. 3 x 2^5 d. 4^60 e. 3 x 4^6 please answer and explain
*August 10, 2014*

**math**

If the number of square inches in the area of a circle is equal to the number of inches in its circumference,the diameter of the circle is a. 4 inches b. 2 inches c. 1 inches d. pi inches e. 2 pi inches please answer and explain
*August 9, 2014*

**math**

I have 10 question like this, anybody can show me this one how to do it. Simplify the following and give answers in scientific notation: 0.00320 x 450,000 / 90,000
*August 8, 2014*

**math**

Write the set of integers that satisfy the sentence: I had 10 question for this,anybody can show this one how to do it. 4 > n > 0
*August 8, 2014*

**math**

In a certain boy's camp, 30% of the boys are from New York State and 20% of these are from New York City.What percent of the boys in the camp are from New York City? a. 60% b. 50% c. 33% d. 10% e. 6% please answer and explain
*August 8, 2014*

**math**

If the number of square inches in the area of a circle is equal to the number of inches in its circumference,the diameter of the circle is a. 4 inches b. 2 inches c. 1 inches d. pi inches e. 2 pi inches please answer and explain
*August 8, 2014*

**math**

If the circumference of a circle is the same as the perimeter of the square with a side as 4 pi in, what is the area of the circle in square inches?
*August 8, 2014*

**math**

I'm just helping my younger brother.
*August 7, 2014*

**math**

so, (2600-440)/4.5=480 answer c, thank you
*August 7, 2014*

**math**

If x = 1/x^2, then 2 + 3 = a. 13/36 b. 1/5 c. 5/6 d. 1/8 e. 5/13 please answer and show work
*August 7, 2014*

**math**

I don't understand what is the question mean
*August 6, 2014*

**math**

The approximate distance,S, in feet that an object falls in t seconds when dropped from a height can be found by using the formula S = 16t^2.In 8 seconds, the object will fall a. 256 feet b. 1,024 feet c. 1,084 feet d. 2,048 feet e. 15,384 feet please answer and explain
*August 6, 2014*

**Physics**

If the thickness of the probe in the direction of B is 1.97 mm, calculate the charge-carrier density (each of charge e).
*August 2, 2014*

**math**

is it answer c. 30 + 7c?
*May 30, 2014*

**math**

why -3 , because the first 3 minutes ?
*May 30, 2014*

**math**

10 cents per minute for the first 3 minutes = 30 cents ,but I don't know what is 10-c cents for each minute thereafter?
*May 30, 2014*

**math**

43. A phone company charges 10 cents per minute for the first 3 minutes of a call, and 10-c cents for each minute thereafter.What is the cost, in cents, of a 10-minute phone call?
*May 30, 2014*

**math**

type mistake: 10 cents per minute for the first 3 minutes = 30 cents
*May 30, 2014*

**math**

10 cents per minute for the first 3 minutes + 30 cents, but I don't know what is 10-cents for each minute thereafter?
*May 30, 2014*

**math**

43. A phone company charges 10 cents per minute for the first 3 minutes of a call, and 10-cents for each minute thereafter.What is the cost, in cents, of a 10-minute phone call? a. 200-20c b.100c+70 c. 30+7c d.100-7c e. 100-70c please answer and explain
*May 30, 2014*

**math**

When a is divided by 7,the remainder is 4.When b is divided by 3,the remainder is 2.If 0<a<24 and 2<b<8, which of the following could have a remainder of 0 when divided by 8? a. a/b b. b/a c. a-b d. a+b e. ab please answer and explain
*May 30, 2014*

**math**

54. The volume of certain rectangular solid is 12x. If the dimensions of the solid are the integers x,y,and z,what is the greratest possible value of z? a. 36 b. 24 c. 12 d. 6 e. 4 please answer and explain
*May 26, 2014*

**math**

When x is divided by 3,the remainder is z.In terms of z, which of the following could be equal to x ? a. z-3 b. 3-z c. 3z d. 6+z e. 9+2z please answer and explain
*May 26, 2014*

**maths**

answer 5
*May 23, 2014*