Velocity of a Falling Object During the construction of a high-rise building, a worker accidentally dropped his portable electric screwdriver from a height of 576 ft. After t sec, the screwdriver had fallen a distance ofs = 16t2 ft. (a) How long did it take the screwdriver to reach the ground? H sec (b) What was the average velocity of the screwdriver between the time it was dropped and the time it hit the ground? ft/sec H (c) What was the velocity of the screwdriver at the time it hit the ground? ft/sec H Need Help? \"arr 11. [/3 Points] TANAPCALC10 2.6.032. ASKYOURTEACHER PRACTICE ANOTHER Velocity of a Hot-Air Balloon A hotair balloon rises vertically from the ground so that its height after t sec is given by the following function. h =%t2+%tftwhere(05t560) (a) What is the height of the balloon at the end of 55 sec? :f't (b) What is the average velocity of the balloon between t = O and t = 55? ft/sec (c) What is the velocity of the balloon at the end of 55 sec? n... , Cost of Producing Surfboards The total cost C(x) (in dollars) incurred by Aloha Company in manufacturing x surfboards a day is given by the following function. C(x) = -10x2 + 500x + 140 where (0 s x s 15) (a) Find C'(x). C' (x ) = (b) What is the rate of change of the total cost (in dollars) when the level of production is 11 surfboards a day? $ per surfboard Need Help? Read It Watch It 13. [-/3 Points] DETAILS TANAPCALC10 2.6.035. MY NOTES ASK YOUR TEACHER PRAC Effect of Advertising on Profit The quarterly profit (in thousands of dollars) of Cunningham Realty is given by P(x) = - _x2 + 4x + 22 (0 5x = 50) where x (in thousands of dollars) is the amount of money Cunningham spends on advertising per quarter. (a) Find P'(x). P' ( X ) = (b) What is the rate of change of Cunningham's quarterly profit if the amount it spends on advertising is $10,000/quarter (x = 10)? (Round your answer to three decimal places.) $ per dollar spent on advertising What is the rate of change if it spends $34,000/quarter (x = 34)? (Round your answer to three decimal places.) $ per dollar spent on advertising