11. Monthly sales revenue, S (in $), and monthly advertising expenditure, A (in $), are modelled by the linear relation, S = 9000 + 12A. (a) If the firm does not spend any money on advertising, what is the expected sales revenue that month?
(b) If the firm spends $800 on advertising one month, what is the expected sales revenue?
(c) How much does the firm need to spend on advertising to achieve monthly sales revenue of $15 000?
(d) If the firm increases monthly expenditure on advertising by $1, what is the corres- ponding increase in sales revenue?
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Describe the domain and range of y=2(3)^x-2+5

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?

In an improper fraction, is the numerator equal to, less than, or greater than the denominator