The height of a right circular cone is 4cm. The radius of its base is 3cm. Find the curved surface area

A.
(9pi cm^2) 
B.
(15pi cm^2) 
C.
(16pi cm^2) 
D.
(20pi cm^2)
Correct Answer: Option B
Explanation
Curved surface area or a cone (=pi rl)
from the information (l^2 = 4^2 + 3^2 = 16+9\
l = sqrt{25} = 5; ∴ C.S.Ahspace{1mm} = frac{22}{7}times 3 times 5\
Since frac{22}{7}=pi ∴ C.S.Ahspace{1mm} =hspace{1mm}15pi)