Well the first thing you have to do is find out how many times 7 goes into 50 whole. This is 7. So then you take the answer to (7x7) from 50 which gives you one, and put it over 50. This equals 7 + 1/50
(a) First find the intersections of

and

:

So the area of

is given by

If you're not familiar with the error function

, then you will not be able to find an exact answer. Fortunately, I see this is a question on a calculator based exam, so you can use whatever built-in function you have on your calculator to evaluate the integral. You should get something around 0.5141.
(b) Find the intersections of the line

with

.

So the area of

is given by


which is approximately 1.546.
(c) The easiest method for finding the volume of the solid of revolution is via the disk method. Each cross-section of the solid is a circle with radius perpendicular to the x-axis, determined by the vertical distance from the curve

and the line

, or

. The area of any such circle is

times the square of its radius. Since the curve intersects the axis of revolution at

and

, the volume would be given by
Answer:
The truck travel must to have a constant speed of 
Step-by-step explanation:
we have

where
d expresses a car's distance in feet
t is the number of seconds
<em>Find the distance d for t=8 sec</em>

<em>Find the distance d for t=8.2 sec</em>

The total distance in this interval of 0.2 sec is

<em>Find the speed of the car</em>
Divide the total distance by the time

therefore
The truck travel must to have a constant speed of 
B is the correct answer I think