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A spherical balloon is being inflated. Find the rate (in ft²/ft) of increase of the surface area (S = 4tr²) with respect to the radius r when r is each of the following. (a) 2 ft (b) 3 ft (c) 5 ft ft²/ft ft²/ft ft²/ft
Suppose that a population of bacteria triples every hour and starts with 400 bacteria. Find an expression for the number n of bacteria after time t hours. n(t) = Use it to estimate the rate of growth of the bacterial population at 3.5 hours. (Round your answer to the nearest whole number.) n'(3.5) = bacteria/hr