10. Find the derivative f'(x) of f (x) = 6x. [A] 6* [B] (In 6)6x [C] In x 6*-1 [D] 6 - 5106 E x6*-1 11. Let y = cot x + sec x. Find y' [A] XZ+ 4 sec x tan x [B] x2 +1 sec x tanx LC] ary + sec x tan x [D] + sec x tan x -2 - sec 2x tan 2x 12. The volume of a sphere is given by V= =ar , with radius r. Which of the following represents the rate of change of the radius ? dr _1 av [A at 4mrz dt [B] at [C] at dy = Anr2 . dr [D] at at [E] = 4mr2 13. If f (x) = x5 + x + 1, find (f ])'(3). Note: The point (1,3) is on the graph of f. [A] 3 [B] 1 [C] 5x* + 1 [D] [E]