An epidemic is growing in a region according to the rate N(t)=66t /t^2+3, where N(t) is the number of people infected after t days. a. Find a formula for the number of people infected after t days, given that 52 people were infected at t=0. b. Use the answer from part a to find the number of people infected after 27 days. Question content area bottom The marginal revenue (in thousands of dollars) from the sale of x gadgets is given by the following function. R(x)=(4x(x^2+28,000)^2/3 a. Find the total revenue function if the revenue from 115 gadgets is $37,271. b. How many gadgets must be sold for a revenue of at least $40,000