B. Because this is an action that is happening that is causing the illness.
1. Using washers, the volume is given by the integral


We're using washers whose centers depend on the value of
, hence we integrate with respect to
2. The area of the given region is given by the integral

To compute the integral, first consider the substitution
, or
so that
. Then
and
, so the integral is equivalently

Integrate by parts, taking


so that

and
, so the area is

For the remaining integral, substitute
, so that
. Then
and
:

(notice that the integral is improper)


Answer:
because he'd seen a tv show about the troubled in schools and lack of qualified teachers. He also wanted to challenge himself.
Posting warning and hazard signs near a pond, fencing your pool, etc etc
So you have to check all angles and x and y axis and then look for the number