A team of medical researchers determined that t days after the epidemic started N(?) = 10t^3 + 5t +√t people would be infected for 0 ≤ t ≤ 20. At what rate did the infected population increase on day 9?

An electric company uses time-of-day pricing to encourage cus- tomers to use electricity during times of less demand. From 6 P.M. to midnight, the cost is modeled by E(t)= 600/(1+t^2) cents per kilowatt hour, where 6 (< or =) t (< or =) 12 is measured in hours after noon. How much does it cost to use one kilowatt of electricity over this 6-hour period?

Let f(x) = [(1000-x)^1/3]. Use linerarization to approximate the number       [(997)^1/3]

You have u= x^(1/2) with x0= $10,000. You can keep this10,000 and gain u = 100 or participate in a game. In this gamble, you can buy a lottery ticket. You might win a prize of 4 million. Lottery operators tell you that there will be N tickets sold. Your chances of winning are π = 1/N. What is the largest number of tickets N that would make you play this game? Briefly explain why N is such a small number. No diagram required.