# Posts by robin

Total # Posts: 404

**Physics**

Grains of fine California beach sand are approximately spheres with an average radius of 50 μm and are made of silicon dioxide, which has a density of 2.4 × 10^3 kg/m3. What mass of sand grains would have a total surface area (the total area of all the individual ...

**Physics**

A severe thunderstorm dumped 2.4 in of rain in 30 min on a town of area 35 km^2. What mass of water (in kg) fell on the town? One cubic meter of water has a mass of 103 kg.

**Can someone plz help me?**

4) The ratio of the number of tickets sold from Jane to Blake is 8:52. Simplify this to get 4/27. 10) Distance between starting line and first aid is 1.25 inches. Convert to miles: 2 inches=50 miles 1 inch=25 miles 1.25=1 mile and a quarter 50/4=12.5 25+12.5=37.5 miles from ...

**Calculus**

How can I get partial sums of a series on a TI 89 calculator?

**Calculus**

Calculate 20 terms for the sequence P0=-.5 and k=1.8, P0=.5 and k=2.8, and P0=.3 and k=1.8. Does the limit depend on the choice of P0? Does it depend on the choice of k?

**science**

what is the centripental acceleration of the car

**Calculus**

Solve the separable differential equation 10x−6ysqrt(x^2+1)dy/dx=0. with the initial condition y(0)=4.

**Calculus**

Determine whether the sequence is divergent or convergent. If it is convergent, evaluate its limit. A (sub n)=((4n-7)/(4n+9))

**Calculus**

Determine whether the sequence is divergent or convergent. a(sub n)=(−1)^n(sin(2/n))

**Calculus**

Solve the seperable differential equation 8yyŒ =x. Use the following initial condition: y(8)=4. Express x^2 in terms of y.

**Calculus**

Find the particular solution of the differential equation particular solution of the differential equation dy/dx=(x−7)e^(−2y).

**Physics**

A machine swings a mass of 1kg connected to a massless rope in a vertical circle so that the speed of them mass is constant at 8 m/s. The rope is 1.0 m long, and the center of the circle is fixed at all times. a) Find the acceleration of the mass with magnitude and direction ...

**Physics**

Massless ropes A, B, C are connected together as shown and support a mass of 100 kg. Rope A is horizontal and ties to the wall, rope b is tied to the ceiling and rope c is vertical. What are the tensions in the ropes.

**Please help with Calculus??**

Boxes are labeled as containing 500g of cereal. The machine filling the boxes produce weights that are normally distributed with standard deviation 12g. 1) Suppose a law states that no more than 5% of a manufacturer's cereal boxes can contain less than the stated weight of...

**READING**

VOCABULAY/CONTEXT CLUES WHAT DOES COMBUSTION MEAN? wHAT CLUES HELP YOU TO DETERMINE THE MEANING? wHAT IS A WAFT? WHAT CLUES HELP YOU TO DETERMINE THE MEANING? HOW DOE CONTEXT CLUES HELP YOU DTERFMINE THE MEANING OF DINGY?

**Calculus**

Awesome! I got .7603 and .142 as my answer. Thank you!

**Calculus**

According to the National Health Survey, the heights of adult males in the United States are normally distributed with mean 69.0 inches and standard deviation 2.8 inches. A. What is the probability that an adult male chosen at random is between 61 inches and 71 inches tall? B...

**Calculus**

A) Find the average value of f(x)=x^3-x+1 on the interval (0,2) B) Find c so that f(c)equals the average value

**statistics**

a sample of 50 women is obtained and their heights (in inches) and pulse rates (in beats per min) are measured. the linear correlation coefficient is 0.229 and the equation of the regression line y= 17.9 +0.870x where x represents hight. the mean of the 50 heights is 63.1 in ...

**Calculus**

x=7t−t^2,y=4t^(3/2) from the point (0,0) to the point (12,32), you'd have to compute integral b to a f(t)dt where a= b= f(t) =

**Calculus Please Help?**

A hawk flying at 25 m/s at an altitude of 150 m accidentally drops its prey. The parabolic trajectory of the falling prey is described parametrically by x=25t,y=150−4.9t^2 until it hits the ground. The variable x represents the horizontal distance traveled by the prey ...

**Calculus**

Determine whether the integral is divergent or convergent. If it is convergent, evaluate it. If it diverges to infinity, state your answer as INF. If it diverges to negative infinity, state your answer as MINF. If it diverges without being infinity or negative infinity, state ...

**Calculus**

A cable hangs between two poles of equal height and 40 feet apart. At a point on the ground directly under the cable and x feet from the point on the ground halfway between the poles the height of the cable in feet is h(x)=10+(0.4)(x^1.5). The cable weighs 18.2 pounds per ...

**MATH - URGENT!!!**

Count Ibis, you are awesome! I loved your explanation too.

**Math**

What is the square root of 693 divided by the sum of pi and Avagadro's number

**Calculus Please Help??**

1. (-5x^2+10x-12)/(x-5)(x^2+4) 2. (-8x-28)/((x-2)(x+9)) I know how to integrate, I just don't know how to get an integral, after finding a,b,c, and from that point

**Calculus Please Help??**

Yes, I know how to get variables. I got b=-8, c=1, and a=2, but I don't know how to get an integral as an answer. I need help integrating 2 other problems I will post as well, if you can help me.

**Calculus Please Help??**

Evaluate the integral (3x^2-16x-19)/(x^3-4x^2-3x+18)

**Calculus**

Snow is falling vertically at a constant rate of 8.0 m/s. At what angle from the vertical do the snowflakes appear to be falling as viewed by the driver of a car traveling on a straight, level road with a speed of 50k.h?

**Calculus**

The position vector for a proton is initially r(with vector sign above it) =5.0i(with top)- 6.0j(with top) + 2.0k(with top) and then later is r vector = -2.0i(with top)+6.0j(with top)+ 2.0k (with top), all in meters. What is the proton's displacement vector, and to what ...

**math**

how much combined tax should be withheld from the paycheck of a married employee earning $910 per week and claiming three withholding allowances.

**math**

Mitch Anderson is a security guard. He earns $7.45 per hour for regular time up to 40 hours, time-and-a-half for overtime, and double time for the midnight shift. If Mitch worked 56 hours last week, including 4 hours on the midnight shift, how much were his gross earnings?

**Maths**

Approximately 1 out of every 4 tax returns contains some type of error. Maria has 260 tax return that she must review how many of these returns are likely to contain error Can someone please help me with this question

**Business**

Tribke Enterprises collected the following data from its financial reports for 2012.........

**MATH**

Create a graph of a function given the following information: The instantaneous rate of change at x = 2 is zero. The instantaneous rate of change at x = 3 is negative. The average rate of change on the interval 0 <x <4 is zero.

**MATH**

A frustrated office worker throws his laptop out of his business’s high-rise office building. The height, h, in meters of the laptop above the ground at t seconds can be modelled by h(t)=125=125-5t^2 Estimate the instantaneous rate at which the laptop hits the ground.

**MATH**

sorry the equation is h(t)=125=125-5t^2

**MATH**

A frustrated office worker throws his laptop out of his business’s high-rise office building. The height, h, in meters of the laptop above the ground at t seconds can be modelled by 2 h(t) 125 5t . Estimate the instantaneous rate at which the laptop hits the ground.

**MATH**

f(x)=3x+2 g(x)=-2x+1 a) Write an equation for ( f+ g)(x) b) Determine (f+g)(6) c) Determine (fg)(6) d) Determine the domain of (f/g)(x)

**MATH**

(1)/(sin(x)-cos(x))=cos(x)+sin(x)

**MATH**

in radians what would the .46 be?

**MATH**

2tan^2x-tanx-1=0 0<x<2pi •MATH - Steve, Thursday, July 18, 2013 at 11:48am (2tanx+1)(tanx-1) = 0 tanx = -1/2 or 1 ... Recall in which quadrants tanx is positive or negative ....................would x= 5pi/6,11pi/6,pi/4 and 5pi/4???

**MATH**

2tan^2x-tanx-1=0 0<x<2pi

**MATH**

A Ferris wheel completes one revolution every 90 s. The cars reach a maximum of 55 m above the ground and a minimum of 5 m above the ground. The height, h, in metres, above the ground can be modeled using a sine function, where t represents time, in seconds. Assume ride starts...

**MATH**

Explain the difference between cos^-1x and (cos x)^-1

**MATH**

Determine an equation of a sinusoidal function that has a maximum at (5, 4) and a minimum at (2, -10).

**MATH**

so ould it be sin pi.6 and tan pi/6??

**MATH**

solve for theda given 0<theda<2pi cos theta= - (sqrt 3)/ 2

**MATH**

Consider the expression logbase5 a=n a) For what value(s) of a will n be a positive number? b) For what value(s) of a will n be a negative number? c) For what value(s) of a will n be undefined?

**MATH**

For what value(s) of x does logbase2 (logbase3 (logbase4 x))=0

**MATH**

Consider the expression logbase5 a=n a) For what value(s) of a will n be a positive number? b) For what value(s) of a will n be a negative number? c) For what value(s) of a will n be undefined?

**MATH**

Given that x=logbase3 5 and y=logbase3 2 , rewrite logbase3 60 in terms of x and y.

**Calculus**

Evaluate the integral below by interpreting it in terms of areas. In other words, draw a picture of the region the integral represents, and find the area using geometry. ç6 −6 36−x^2dx

**Calculus**

For the function f described by the following table, estimate ç40 0 f(x)dx using the following. Enter each answer as a sum to show your work. 5 left rectangles 5 right rectangles 5 midpoint rectangles x 0 4 8 12 16 20 24 28 32 36 40 y 7 -46 -50 45 -7 -26 23 -3 18...

**Calculus**

Consider the function f(x)=(8)/(x^2)−(8)/(x^5) . Let F(x) be the antiderivative of f(x) with F(1)=0. Then F(2) equals ?

**Calculus**

Find the point on the line 7x+5y−2=0 which is closest to the point (−6,−2).

**Calculus**

A rancher wants to make a rectangular pen to house her animals. She will divide it up with 3 fences down the middle parallel to one side. If she has 14000 ft of fencing to work with, what are the dimensions of the pen of greatest area? Width = Length = What is the greatest ...

**Calculus**

Find the point on the line 7x+5y−2=0 which is closest to the point (−6,−2).

**Please help with Calculus problem??**

A particle moves with a fixed acceleration 3 m/s^2. If its initial velocity is s(0)=0: a) Find its velocity function. b) How long does it take for the particle to reach the velocity 14 m/s^2? c) Find the distance the particle traveled when its velocity reaches 14 m/s^2.

**Calculus**

Find the absolute maximum and the absolute minimum values of f(x)=x−7cos(x) on the interval [−ð,ð).

**Calculus**

Gravel is being dumped from a conveyor belt at a rate of 10 cubic feet per minute. It forms a pile in the shape of a right circular cone whose base diameter and height are always equal. How fast is the height of the pile increasing when the pile is 16 feet high? Recall that ...

**Please help with Calc problem??**

Sorry, I meant a television camera is positioned 2500 ft from the base of a rocket launching pad. The angle of elevation of the camera has to change at the correct rate in order to keep the rocket in sight. Also the mechanism for focusing the camera has to take into account ...

**Please help with Calc problem??**

The angle of elevation of the camera has to change at the correct rate in order to keep the rocket in sight. Also the mechanism for focusing the camera has to take into account the increasing distance from the camera to the rising rocket. Let's assume the rocket rises ...

**Calculus**

A television camera is positioned 2500 ft from the base of a rocket launching pad. The angle of elevation of the camera has to change at the correct rate in order to keep the rocket in sight. Also the mechanism for focusing the camera has to take into account the increasing ...

**Calculus**

Two cars start moving from the same point. One travels south at 60 mph and the other travels west at 25 mph. At what rate is the distance between the cars increasing 2 hours later? Let x = the distance covered by the south traveling car. Let y = the distance covered by the ...

**Calculus**

A television camera is positioned 2500 ft from the base of a rocket launching pad. The angle of elevation of the camera has to change at the correct rate in order to keep the rocket in sight. Also the mechanism for focusing the camera has to take into account the increasing ...

**Calculus**

Let y=e^(x/9). a) Find the differential dy. dy = b) Evaluate dy if x=0 and dx=−0.03. dy =

**Math**

How would you do this problem. What is the growth rate of the stock with a $3.00 expected dividend and a $20.60 price with 15%required return?

**math**

R. H. Bruskin Associates Market Research found that 30% of Americans do not think that having a college education is important to succeed in the business world. If a random sample of five Americans is s selected, find these probabilities. (a) Exactly two people will agree with...

**Calculus**

The motion of a spring that is subject to dampening (such as a car's shock absorber)is often modeled by the product of an exponential function and a sine or cosine function. Suppose the equation of motion for a point on such a spring is s(t)=3∗e^(−2t)sin(3ð...

**Calculus**

Find the outside and inside functions of the following to find their derivatives: 1) sqrt(2x+9) 2) cos(cos(x)) 3) tan(x) I already know how to find their derivatives I'm just not exactly sure what parts of the chain rule equation would be considered the outside and inside.

**Calculus**

For what values of x with 0¡Üx¡Ü2¦Ð does the graph of f(x)=x+4sin(x) have a horizontal tangent?

**Calculus**

Find the equation of the tangent line to the curve y=2tan(x) at the point (pi/4,2).

**Calculus**

Sketch a graph of the parabola y=x^2+3. On the same graph, plot the point (0,−6). Note there are two tangent lines of y=x2+3 that pass through the point (0,−6). The tangent line of the parabola y=x^2+3 at the point (a,a^2+3) passes through the point (0,−6) ...

**Calculus**

Find the values of a ,b, and c in the quadratic function p(x)=ax^2+bx+c such that p(2)=6, p'2)=2, and p''(2)=3. a = b = c =

**Calculus**

Find the values of a , b , and c in the quadratic function p(x)=ax2+bx+c such that p(2)=6, p'(2)=2, p"(2)=3

**Calculus**

Find the values of a , b , and c in the quadratic function p(x)=ax^2+bx+c such that p(2)=6, pŒ(2)=2, and pŒŒ(2)=3.

**Calculus**

Find an equation for the tangent line of the function f(x)=6+10xe^x at the point (0,6).

**Calculus**

Find an equation for the tangent line of the function y=x+(4/x) at the point (2, 4). The equation of the tangent line is . You may enter the equation in any form.

**Calculus**

Let f(x)=−4−3x+2x^2. Use the limit definition of the derivative to find find fŒ(a)

**Calculus**

If a ball is thrown straight up into the air with an initial velocity of 95 ft/s, its height in feet after t seconds is given by f(t)=95t−16t^2 Find the average velocity for the time period beginning when t=1 and lasting (i) 0.5 seconds (ii) 0.1 seconds (iii) 0.01 ...

**Physics**

A roller coaster has a mass of 425 kg. It sits at the top of a hill with height 66 m. If it drops from this hill, how fast is it going when it reaches the bottom? (Assume there is no air resistance or friction.)

**chemistry**

The reaction of chlorine gas with solid phosphorus (P4) produces solid phosphorus pentachloride. When 63.5 g chlorine reacts with 28.5 g P4, which reactant is limiting?

**statistics**

if no preliminary sample is taken to estimate p, how large a sample is necessary to be 87% sure that the point estimate will be within a distance of 0.04 from p?

**PHYSICS**

A 2kg block is on a level table and held against a spring with k =150N/m which has been compressed 15 cm. he block is released from rest and pushed across the table. When the block leaves the spring it beins to experience fricion with coeficient of 0.25. What is the total ...

**PHYSICS**

yes would you be able to show me?

**maths literacy,business studies, tourism, economic**

What kind of work can i get one day with this subjects and what is the salary?

**math**

the original question was x^2-4x=32 can you help me solve?

**math**

x^2-4x+32=0. would the final answer be 2 +or- 2 sqrt7 ?

**math**

Thank you!

**math**

I am working on quadratic equations and I have worked a problem down to 3 plus or minus the square root of 361 all over 2... what next?

**Physics true false**

true false The speed of a particle is always positive. True False The average speed of a particle is equal to the magnitude of its average velocity. True False The acceleration of a particle can be non-zero when its speed is constant. True False When the average velocity of a ...

**Geography**

Hydrosphere basic facts and what makes up the hydrosphere?

**Chemistry**

two solutions are prepared using the same solute solution a: 0.27g of the solute disolves in 27.4g of t-butanol solution b: 0.23g of the solute disolves in 24.8g of cyclohexane which solution has the greatest freesing point change? show calculations and explain.

**Chemistry**

two solutions are prepared using the same solute solution a: 0.27g of the solute disolves in 27.4g of t-butanol solution b: 0.23g of the solute disolves in 24.8g of cyclohexane which solution has the greatest freesing point change? show calculations and explain.

**Math**

Rearrange this expression into quadratic form, ax2 bx c = 0 0.20= ((x^2)/(55-x)) where a = 1, and identify the values of b and c.

**grammar, contractions and negatives**

No one, or Someone who bought a car for transportation was not considered sane.

**math**

3 pumps, working 6 hours a day, can empy a water tank in 2 days. How many hours a day must 9 pumps work to empty the same tank in 1 day?

**Math**

A room is 45 m x 15 m. What is the least number of rectangle tiles required to pave the floor of the room, if each tile is 50 cm x 1m?

**Geology**

There is also a graph i can't move it. Building Isochrons and Determining the Ages of Three Rocks Page 15 of 17 For each of the three rocks listed below follow these steps to determine the rock's age of formation. 1. Prepare an isochron by plotting the points that ...