(C)
Step-by-step explanation:
The volume of the conical pile is given by

Taking the derivative of V with respect to time, we get


Since r is always equal to h, we can set

so that our expression for dV/dt becomes


Solving for dh/dt, we get



$18.75 hours at $7.85 pet hour is exactly 1471875, moving the decimal 4 places to the left and round to the nearest penny is
$147.1875 Or $147.19
You swap x and y. for example, the first set is (0,1) so the inverse would be (1,0)