Sunday

October 23, 2016
Total # Posts: 1,494

**Calculus- Can you help me solve for dr/dt**

How fast does the radius of a spherical soap bubble change when you blow air into it at the rate of 15 cubic centimeters per second? Our known rate is dv/dt , the change in volume with respect to time, which is 15 cubic centimeters per second. The rate we want to find is dr/dt...

*December 29, 2014*

**math**

The ratio of the monthly incomes of A and B is 3:4. The ratio of monthly expenditures of A and B is 4:5. Which of the below is a possible value of the ratio of their savings? 9:10 3:4 13:20 4:5 How to form a equation for solving this?

*December 19, 2014*

**math**

The ratio of the monthly incomes of A and B is 4:3 . The ratio of their monthly expenditures is 5:4 . If A saves one fourth of his monthly income, find the ratio of their monthly savings. Help me solving this please!!

*December 19, 2014*

**English **

To what extent to schools need more structure and discipline? Any opinions??

*December 14, 2014*

**Physics**

A bowling ball slows down at rate of .12 m/s^2. 5 seconds after it starts down the bowling alley its speed is 15 m/s. What was its initial speed?

*December 13, 2014*

**AP CaLC. AB**

if you fold it it will create a right triangle. x is the base and y is the height.

*December 13, 2014*

**AP CaLC. AB**

The upper left-hand corner of a piece of paper 8 in. wide by 17 in. long is folded over to the right-hand edge. How would you fold it so as to minimize the length of the fold? In other words, how would you choose x to minimize y?

*December 13, 2014*

**English**

Opinions please??

*December 10, 2014*

**English**

How much control should students have over their education?

*December 10, 2014*

**English**

Amelia was too tired to walk her dog, after running the half marathon. Is that right? And thank you.

*December 9, 2014*

**English **

Rewrite the following sentences in order to correct the punctuation. In the morning Shelby ate a peanut butter sandwich and an apple she rode her bike to school. After running the half marathon; Amelia was too tired to walk her dog.

*December 9, 2014*

**math**

John and Smith went to a stationery shop. John bought 6 pens, 4 pencils and 3 erasers. Smith bought 3 pens, 8 pencils and 6 erasers and spent 20% more than John. What percentage money did John spend on pens? How can I form an equation and solve?

*December 8, 2014*

**math**

The sum of two numbers is 4 and the reciprocal of one exceeds the reciprocal of other by twice the product of their reciprocals. What is the product of the reciprocals of two numbers? Please help me solving.

*December 8, 2014*

**chemistry**

The number of protons in an anion must always be ________ the number of electrons. the same as We can’t tell. less than greater than

*December 6, 2014*

**chemistry**

A metal oxide will form an acid when it is dissolved in water. T/F

*December 6, 2014*

**chemistry**

When an acid and a base react in a neutralization reaction, the products will be acidic. T/F

*December 6, 2014*

**Chemistry**

Temperature is a measure of the amount of heat an object contains. T/F

*December 6, 2014*

**Chemistry**

An archeological artifact was subjected to radiocarbon dating. The artifact showed a carbon-14 decay rate of 13.8 disintegrations/ min per gram of carbon. Carbon-14 has a half-life of 5715 years, and currently living organisms decay at the rate of 15.3 disintegrations/ min per...

*December 5, 2014*

**math**

I don't know

*December 4, 2014*

**math**

A test had 200 questions .Each correct answer carried 2 marks.Each wrong answer carried -1/2 marks and unanswered question fetched no marks .Ajay attempted all the question in the test and he scored 360 marks.What would his marks be, if for each correct answer he got 1/2 marks...

*November 28, 2014*

**AP CALC. AB**

1. Let f be the function given by f(x)=x^2+4x-8. The tangent line to the graph at x = 2 is used to approximate values of f . For what value(s) of x is the tangent line approximation twice that of f ? I: -√2 II: 1 III: √2 Select one: a. III only b. I and III only c...

*November 26, 2014*

**Algebra **

What is the range of the function f(x)=3-2*51^x? Give your answer as an interval.

*November 21, 2014*

**Math**

Hi Reiny, Thank you for answering my question, but I don't think there is ã2 at the top because, my teacher said it is just supposed to be whole numbers in the denominator and numerator.

*November 21, 2014*

**Math**

No problem.

*November 20, 2014*

**Math**

10 divided by 4/5 is the same thing as multiplying it's reciprocal. 10 * 5/4 = 50/4 (All you have to do is flip 4/5 to 5/4) You can simplify 50/4 to 12 1/2.

*November 20, 2014*

**Science **

What would happen if cells didn't have the following? : -Nucleus -Ribosomes -Endoplasmic Reticulum -Cell Wall

*November 20, 2014*

**Algebra**

A kite is tied to the ground. The rays from the sun hit the kite perpendicular to the kite string, casting a shadow of the kite on the ground. The coordinates in the diagram are given in feet. What is the distance from where the kite is tied to the shadow? Coordinates are (3,...

*November 19, 2014*

**Statistic**

A major airline company is concerned that its proportion of late arrivals has substantially increased in the past month. Historical data shows that 18% of the company airplanes have arrived late. In a random sample of 1,240 airplanes, 310 airplanes have arrived late. a. ...

*November 17, 2014*

**Cal-help-Plz?**

Me confuseddd

*November 16, 2014*

**Cal**

Which of the following functions is continuous but not differentiable at x = 1? Functions: I.y=3√x-1 II.y={x^2,x≤1 2x,x>1 III. y={x,x≤1 1/x,x>1 I'm not really sure how to do this, but I've been trying and I keep getting both I and III.. am I ...

*November 16, 2014*

**CAL**

Okay I sure will! Thanks

*November 16, 2014*

**CAL-Reinyyy**

The equation is y= x cubed over x minus x so; y= x^3 / x -x Sorry for being confusingg

*November 16, 2014*

**AP CALC. AB**

A particle moves along a line so that at time t, where 0<=t<=pi, its position is given by s(t)= -4cost-((t^2)/2)+10 What is the velocity of the particle when its acceleration is zero? a. 8.13 b. 1.32 c. 0.74 d. -5.19 e. 2.55 I know that c and b are incorrect Please help me

*November 16, 2014*

**Algebra**

I don't understand

*November 14, 2014*

**Algebra**

What is the equation in the slope intercept form for the line that passes through the points (1,-3) and (3,1)? Y=3x+1 Y=x-3 Y=2x+5 Y=2x-5

*November 14, 2014*

**Algebra**

What is an equation in slope intercept form for the line that passes through the points (1,-3) and (3,1)?

*November 13, 2014*

**AP CALC. AB**

I am really confused on part 1. I don't even know what u did. For part 2 where did u get .75 and did you mean to solve for dh/dt

*November 7, 2014*

**AP CALC. AB**

Please help me with this problem and please walk me through each step i am really confused. Sand is falling from a rectangular box container whose base measures 40 inches by 20 inches at a constant rate of 300 cubic inches per minute. a) how is the depth of the sand in the box...

*November 7, 2014*

**AP Calc. AB**

If f(x)=2x+sin(x) and the function g is the inverse of f, then g'(2)=?? a. 0.40 b. 0.38 c. 0.34 d. 0.32 e. 0.36

*November 1, 2014*

**Finance**

The 6 percent, semi-annual bonds issued by Black Water Mills mature in 9 years and have a face value of $2,200. What is the current value of one of these bonds if the market rate of return is 11.10 percent?

*October 29, 2014*

**Chemistry**

do you know anyone who can help me with those questions if you do can you please let them know thanks

*October 27, 2014*

**Chemistry**

the one that says science rachel

*October 27, 2014*

**Chemistry**

did you write anything because it doesnt show

*October 27, 2014*

**science**

drbob222 can you please answer the science questions on my post

*October 27, 2014*

**science**

do you know anyone who can help me?

*October 27, 2014*

**science**

dr bob 222 or ms.sue can you please answer these questions

*October 27, 2014*

**math**

which number has the greatest value? a 3.5 b square root of 15** c square root of 1/16 d 26/100 which number is an irrational number? a 3.5 b square root of 36 c square root of 48 d 37/100*** If a is a rational number and b is an irrational number, then the sum a + b is A)...

*October 27, 2014*

**science**

1. Tommy performed an experiment to test the solubility of sodium chloride in water. After he completed his experiment, he discovered that he had a few unused grams of NaCl leftover in a beaker. What should he do with the excess NaCl? A. Pour the excess back into the original ...

*October 27, 2014*

**AP Calc. AB**

If f and g are functions such that f(g(x))=g(f(x))=x for all x in their domains, and if f(a)=b and f'(a)=c, then g'(b) =? a) g'(a)=1/c b) g'(b)=1/c c) g'(b)=-1/c d) g'(b)=1/a e) g'(a)=-1/c

*October 26, 2014*

**Chemistry**

3NO2(g) + H2O(l) → 2HNO3(aq) + NO(g) standard enthalpy: -133.5 Find the change in internal energy for this reaction. Enter in kJ.

*October 21, 2014*

**Statistics**

Suppose a certain species bird has an average weight of grams. Based on previous studies, we can assume that the weights of these birds have a normal distribution with grams. For a small group of 13 birds, find the margin of error for a 70% confidence interval for the average ...

*October 19, 2014*

**US History **

This is a letter from George Washington to Patrick Henry: September 24, 1787 I don't understand what his purpose and point of view is. Please help me!!! Dear Sir: In the first moment after my return I take the liberty of sending you a copy of the Constitution which the ...

*October 19, 2014*

**AP CALC. AB**

1.The position of a particle moving on the line y = 2 is given by x(t)= 2t^3-13t^2+22t-5 where t is time in seconds. When is the particle at rest? a. t =0.268, 2.500, and 3.732 b. t = 0, 1.153, and 3.180 c. t = 1.153, 2.167 and 3.180 d. t = 2.167 e. t = 1.153 and 3.180 2.A ...

*October 12, 2014*

**physics**

A cyclist maintains a constant velocity of 4.1 m/s headed away from point A. At some initial time, the cyclist is 244 m from point A. What will be his displacement from his starting position after 60 s?

*October 10, 2014*

**Economics**

explain why positive and negative externalities are market failures

*October 9, 2014*

**US History **

The Revolutionary War could be considered an international war. Explain if this statement is true or false using examples.

*October 7, 2014*

**US History **

Were the colonists politically independent before the French and Indian War?

*October 6, 2014*

**US History**

the seven years of war led to taxation without representation because of the debt that king george had to pay for. therefore this angered the colonies and was a turning point to english and colonists relationships

*October 5, 2014*

**US History**

i am writing an essay so i need to write about multiple reasons

*October 5, 2014*

**US History**

taxation without represent ions that the only one that i know

*October 5, 2014*

**US History **

Why was seven years of war a turning point in British colonial society and their relationship with England? Please give me 4 different reasons.

*October 5, 2014*

**physics**

A diver achieves a horizontal velocity of 3.76 m/s from a diving platform located 6m above the water. How far from the edge will the diver be when she hits the water?

*October 5, 2014*

**AP CALC. AB**

Let f(x)=3/x. If the rate of change of f at x = c is three times its rate of change at x = 2, then c = ?

*October 3, 2014*

**AP Calc. AB**

At how many points on the curve y=4x^5-3x^4+15x^2+6 will the line tangent to the curve pass through the origin?

*October 3, 2014*

**Social Studies**

angel, which answer did you get wrong?

*October 3, 2014*

**AP Calc. AB**

1.If an arrow is shot upward on the moon with a velocity of 50 m/s its height (in meters) after t seconds is given by H = 50t - 0.66t2. With what velocity will the arrow hit the moon? a. -49.5 b. -47 c. -50.1 d. -50 e. -51 2.If an arrow is shot upward on the moon with a ...

*September 28, 2014*

**math statistics**

A group of teenager smoking rate dropped 8.5% in 2007 from 17.6% in 2001 and 23% in 1997. 1. Calculate the probability that at least one in a group of 10 teenagers smoked in 2007.2. Calculate the probability that at least one in a group of 10 teenagers smoked in 2001. 1. ...

*September 23, 2014*

**statistics**

Teenage smoking rate dropped to 8.5% in 2007 from 17.6% in 2001 and 23% in 1997. 1. Calculate the probability that at least one in a group of 10 teenagers smoked in 2007. 2. Calculate the probability that at least one in a group of 10 teenagers smoked in 2001. 3. Calculate the...

*September 23, 2014*

**AP Calc. AB**

is it 57 m/s??

*September 21, 2014*

**AP Calc. AB**

If an arrow is shot upward on the moon with a velocity of 57 m/s its height (in meters) after t seconds is given by H= 57t-0.06t^2. With what velocity will the arrow hit the moon?

*September 21, 2014*

**AP Calc. AB**

Thanks Steve ur a life saver!!

*September 21, 2014*

**AP Calc. AB **

1.Which function is NOT continuous everywhere? A.y=(4x)/(x+1)^2 B.y=|x| C.y=(x)/(x^2+1) D.y=√(x^2+1) E.y=x^(2/3) 2.State the domain f(x)= √((x+6)) sinx 3. Let h(x) {(sin2x)/x, if x ≠ 0 {a, if x=0 find the value of a so that hi s continuousat x=0 a. it is sot ...

*September 21, 2014*

**US History**

What factors made New England so different from the middle and southern colonies? Consider such things as economics, environment, social make up, philosophy, and religion?

*September 21, 2014*

**US History**

Thank You!!!

*September 17, 2014*

**US History **

Why is the landing at Plymouth Rock seen as just as important as Jamestown, or more so, in the founding of our country?

*September 17, 2014*

**English**

Would just in this sentence be considered and adverb? Now when they were first made, the bears were covered with hair and had sharp claws. Would this be an example of adverb modifying a verb

*September 14, 2014*

**algebra**

Find the center and radius of the circle whose equation is 5x^2−6x+5y^2+8y−9=0.

*September 14, 2014*

**algebra**

Find the domain and range of: F(x)=sqrt(x)+16

*September 14, 2014*

**English**

What is the tone in When Grizzlies Walked Upright?

*September 14, 2014*

**Biology**

Is respiratory control more sensitive to small changes in arterial PO2 or in arterial PCO2?

*September 8, 2014*

**Biology - very urgent**

Is respiratory control more sensitive to small changes in arterial PO2 or in arterial PCO2?

*September 8, 2014*

**Marketing**

How would you classify Wal-Mart in terms of its position on the wheel of retailing versus that of an off-price retailer?

*September 7, 2014*

**Math**

At Lucy's Restaurant,1 3/4 a serving of tomato soup is cups. Lucy makes 63 cups of tomato soup each day. How many servings of tomato soup does she make?

*August 26, 2014*

**Chemistry**

Calculate the concentrations of all species in a 1.17 M Na2SO3 (sodium sulfite) solution. The ionization constants for sulfurous acid are Ka1 = 1.4× 10–2 and Ka2 = 6.3× 10–8. I found Na+ = 2.34 SO3^2- = 1.17 H2SO3 = 7.14 x10^-13 I can't find HSO3...

*July 21, 2014*

**Chemistry**

Phosphoric acid, H3PO4(aq), is a triprotic acid, meaning that one molecule of the acid has three acidic protons. Estimate the pH, and the concentrations of all species in a 0.200 M phosphoric acid solution. pKa1 = 2.16 pKa2 = 7.21 pKa3 = 12.32 Ok I haven't been able to ...

*July 21, 2014*

**analytic geometry**

the three vertices of a triangle are at A (-4,5), B(-5,3) and C (3,-4), show that the line joining the midpoint of the sides AC and BC is parallel and equal to one-half of AB . solve

*July 16, 2014*

**analytic geometry**

the three vertices of a triangle are at A (-4,5), B(-5,3) and C (3,-4), show that the line joining the midpoint of the sides AC and BC is parallel and equal to one-half of AB . solve

*July 16, 2014*

**science**

A comet is in an elliptical orbit around the Sun. Its closest approach to the Sun is a distance of 4.8 x10^10 m (inside the orbit of Mercury), at which point its speed is 9.1 x10^4 m/s. Its farthest distance from the Sun is far beyond the orbit of Pluto. What is its speed when...

*July 8, 2014*

**math**

what is the integral from 2 to 1 of 15sqrt(4x^2-3) dx

*July 2, 2014*

**science**

A 25 kg box is being pushed across the floor by a constant force ‹ 100, 0, 0 › N. The coefficient of kinetic friction for the table and box is 0.15. At t = 6.0 s the box is at location ‹ 14, 3, −4 › m, traveling with velocity ‹ 6, 0, 0 › m/s...

*June 30, 2014*

**Chemistry**

Fish breathe the dissolved air in water through their gills. Assuming the partial pressures of oxygen and nitrogen in the air are to be .20 atm and .80 atm respectively, calculate the mole fractions of oxygen and nitrogen in the air dissolved in water at 298 k. The ...

*May 31, 2014*

**geometry**

Ralph the monkey is looking down at a 31° angle from the top of a tree. There are bananas on the ground 12.4 ft from the base of the tree. If Ralph flies down from the tree at a diagonal path, shown in the diagram by x, what distance would he travel? Round to the nearest ...

*May 29, 2014*

**maths**

calculate the values of p and q Analytical geometry

*May 18, 2014*

**physics**

A moving object has a kinetic energy of 147 J and a momentum of 22.3 kg·m/s. a) Find the speed of the object. Answer in units of m/s

*May 1, 2014*

**Chemistry**

A small pebble is heated and placed in a foam cup calorimeter containing water at 25 °C. The water reaches a maximum temperature of 27 °C. If the pebble released 532.1 J of heat to the water, what mass (in g) of water was in the calorimeter? can you show me what ...

*May 1, 2014*

**Chemistry**

A small pebble is heated and placed in a foam cup calorimeter containing water at 25 °C. The water reaches a maximum temperature of 27 °C. If the pebble released 532.1 J of heat to the water, what mass (in g) of water was in the calorimeter?

*April 30, 2014*

**Chemistry**

If 82.4 g of cold water (initially at 22 °C) is mixed in an insulated container with 96 g of hot water (initially at 88 °C), what will be the final temperature of the water in °C?

*April 30, 2014*

**Calculus**

if the work required to stretch a spring 1 ft beyond its natural length is 12 ft-b, how much work is needed to stretch 9 inches beyond its natural length?

*April 30, 2014*

**Math**

A ball is thrown downward from the top of a 100-foot building with an initial velocity of 14 feet per second. The height of the ball h after t seconds is given by the equation h=-16t^2-14t+100. How long after the ball is thrown will it strike the ground?

*April 28, 2014*

**Algebra**

How can I solve 1/2x+1/x=-12?

*April 16, 2014*