It's basically 5,000*2=10,000
and 10,000/2=5,000. your answer would be either they multiplied 5,000 by 2 and 10,000 divided by 2, they increased the sales by 5,000
a.
has an average value on [5, 11] of

b. The mean value theorem guarantees the existence of
such that
. This happens for

Option C:
is the value of a and b
Explanation:
Given that the expression 
We need to determine the value of a and b
Let us consider the term
and take the prime factorization of the term 648
Thus, we have,
648 divides by 2,

324 divides by 2,

162 divides by 2,

81 divides by 3,

27 divides by 3,

9 divides by 3,

Thus, we have,

Therefore, equating the powers of 2 and 3, we get,

Hence, the value of a and b is 3 and 4
Thus, Option C is the correct answer.
So hmmm check the picture below
so, we're looking for dr/dt then at 4:00pm or 4 hours later
now, keep in mind that, the distance "x", is not changing, is constant whilst "y" and "r" are moving, that simply means when taking the derivative, that goes to 0