Mr. Pablo owns an apartment building with 60 rooms. he can rent them all if he sets a monthly rent of $ 200 per room. With a higher rent, some rooms would be left empty. On average, for every $ 5 rent increase, a room would be left empty with no possibility of rent. Determine the functional relationship between total monthly income and the number of empty rooms. What monthly rent will maximize the total income? What is this maximum income?

Ineed i don’t get this at all! and you

If c(x) = 4x – 2 and d(x) = x2 + 5x, what is (cxd)(x)

Quick! a survey of 57 customers was taken at a bookstore regarding the types of books purchased. the survey found that 33 customers purchased mysteries, 25 purchased science fiction, 18 purchased romance novels, 12 purchased mysteries and science fiction, 9 purchased mysteries and romance novels, 6 purchased science fiction and romance novels, and 2 purchased all three types of books. a) how many of the customers surveyed purchased only mysteries? b) how many purchased mysteries and science fiction, but not romance novels? c) how many purchased mysteries or science fiction? d) how many purchased mysteries or science fiction, but not romance novels? e) how many purchased exactly two types of books?