1) Business: Revenue, Cost, and ProfitThe cost, in dollars, to a company to pro-

duce x units of a product is modeled by the function C(x) = 0.02x 3 0.5x 2 + 10x + 50The revenue, in dollars, the company expects from the sale of x units of the

product is modeled by

R(x) = 1.1x 2 + 41.5x

The profit, in dollars, realized on the sale of x units of the product is just the revenue minus the cost, that is,

P(x) = R(x) C(x)

a. Construct a model for the profit function. B. Find the profit when the number of units sold is 19.C. Find the profit when the number of units sold is 20. D. Find the profit when the number of units sold is 21. E. What is the trend in the profit as the number of units produced and sold

increases from 19 through 21

2)Health Science: Carbon Monoxide LevelsA study of a northwestern community

indicates that the average daily level C of carbon monoxide in the air, in parts per million (ppm), is approximated by the function

C(p) = square root 0.18p2 + 9.60 < p 20

where p represents the population of the community in thousands of people.(Enter this function using Y1.) The population of the community depends on the time t in years from now and is approximated by the function

p(t) = 1.8 + 0.04t 20 < t 20

(Enter this function using Y2.) Compute the level of carbon monoxide in this community's air 15 years from now in two ways. First, compute p(15) and then substitute this result into C(p). Second, compute C[p(15)] directly using the method shown in Example 6. Compare the two results. If they are equal,write your conclusion in sentence form. If they are unequal, try again..