In 1990, Nigeria had a population of about 95.3 million. By 2000, there were about 122.4 million people, an increate of about 28.4%. During that decade, the populatio can be reasonably modeled by an exponential function. Express the population of Nigeria f(d), in millions of people, d decades since 1990.

the revenue of the fitness center, y, is the product of two factors: the number of members and the fee paid by each member. there are 320 members now, but number of members goes down by 10 for each $5 increase in fees, so if x is the number of $5 price increases then members is equal to (320 - 10x). since the fee is currently $45, and the fee increases by $5 for every price bump x, the fee is given by (45 + 5x). so, revenue y is given by y = (320 - 10x)(45 + 5x).