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An object is dropped from a tower, 175 ft above the ground. The object's height above ground t see into the fall is s =175 16t2. a. What is the object's velocity, speed, and acceleration at time t? b. About how long does it take the object to hit the ground? 0. What is the object's velocity at the moment of impact? The accompanying figure shows the velocity The body reverses direction at t = ds V= Use a comma to separate answers dt = f(t) (m/sec) of a body moving along a as needed.) coordinate line. a. When does the body reverse direction? b. When is it moving at a constant speed? c. Graph the body's speed for Osts 10. d. Graph the acceleration, where defined. . . . Av (m/sec) 5- + v = f(t) (sec) 6 8 40Suppose that the dollar cost of producing x appliances is c(x) = 1100 +140): 0.4x2. a. Find the average cost per appliance of producing the first 150 appliances. b. Find the marginal cost when 150 appliances are produced. c. Show that the marginal cost when 150 appliances are produced is approximately the cost of producing one more appliance after the rst 150 have been made, by calculating the latter cost directly. When a bactericide is added to a nutrient broth in which bacteria are growing, the bacterium population continues to grow for a while, but then stops growing and begins to decline. The size of the population at time t (hours) is b = 68 + 67t 653. Find the growth rates at t=0 hours, t= 3 hours, and 1:: 6 hours. 4 The volume V = Ems of a spherical balloon changes with the radius. a. At what rate (inSIin) does the volume change with respect to the radius when r = 3 in? b. Using the rate from part a, by approximately how much does the volume increase when the radius changes from 3 to 3.2 in