D. because PQR and XYZ are not congruent
Given cost function is
c(x) = 
(20 ≤ x ≤ 400)
where x is the number of thousands of square feet
total revenue will be $0.2 million dollars per thousand square feet
Revenue is 0.2 millions per thousand square feet. we know x is the number of thousand of square feet
So R(x) = 0.2x
We know Profit = Revenue - Cost
P(x) = R(x) - C(x)
combine like terms
Profit function is
The surveyor selects the twentieth student who enters the building. The student do not enter the building to be surveyed but for other reasons and the researcher take advantage of that and selects them. This is a form of continence sampling.
The researcher selects every twentieth student and not any other. Therefore, the sampling is systematic in nature.
Finally, students selected to participate in the survey are free to choose if to participate in he survey or not. Therefore, it is voluntary kind of sampling.
Therefore, the applicable sampling methods are convenience, systematic, and voluntary.
The difference between consecutive integers is 1.
Let x = smaller integer.
Then x + 1 is the next greater consecutive integer.
x(x + 1) = 132
x^2 + x - 132 = 0
(x + 12)(x - 11) = 0
x + 12 = 0 or x + 11 = 0
x = -12 or x = -11
Since x is the smaller of the two integers, the answers are:
-12, -11
11, 12
There are two pairs of such integers.
Simply 8. 8 fits into 2 4 times.
