Answer:
16.822 I think
Step-by-step explanation:
Answer: x=8 x=0
Step-by-step explanation:
Answer:

which is the first option in the list of possible answers.
Step-by-step explanation:
Recall that the minimum of a parabola generated by a quadratic expression is at the vertex of the parabola, and the formula for the vertex of a quadratic of the general form:

is at 
For our case, where
we have:

And when x = 1, the value of "y" is:

Recall now that we can write the quadratic in what is called: "vertex form" using the coordinates
of the vertex as follows:

Then, for our case:

Then, for the quadratic equal to zero as requested in the problem, we have:

AnswerdV/dt = 4·pi·(40)2·(-2)
Step-by-step explanation: