Q8.9

Question 8 (5 points) Solve the problem. How much work is done by a 140-lb woman as she walks up 12 steps, each with a = -ft rise? O A) 420 ft . lb O B) 1680 ft . lb C) 840 ft . lb OD) 3360 ft . lb Question 9 (5 points) Find the volume of the solid generated by revolving the region R bounded by the graphs of the given equations about the y-axis. 3TL x = 2tan 3 , x = 0, y = - 4 O A) 6TI - 31 2 O B) 37 + 371 2 O C) 12 - 37 O D) 12 T - 371 2