The lateral surface area of a right circular cone of height 28 cm and base radius 21 cm is:
2110 cm2
2310 cm2
1155 cm2
1055 cm2
Given, h = 28 cm; r = 21 cm
Therefore, slant height (l) = √282+212
= 35 cm
Lateral surface area = πrl
= 227 × 21 × 35
= 2310 cm2