17) What is the surface area of following figure?
(A) 33 π
(B) 24 π
(C) 25 π
(D) 11 π
18) In the figure below, given that AD = 6, CD = 8, AE = x. What is the area of the shaded region?
(A) 28 - 2x
(B) 4(14 - 4x)
(C) 48 - 3x
(D) 7(6 - 3x)
19) If the radius of the circle is decreased by 20%, than the area
(A) increases by 10%
(B) decreases by 20%
(C) increases by 80%
(D) decreases by 36%