Radius of the cone is 6 unit.
Step-by-step explanation:
Given:
Lateral Surface Area of Cone, LSA = 100π unit²
Total Surface Area of cone, TSA = 136π unit²
Let, r be the radius of cone.
According to the question,
Total Surface area = lateral surface area + Area of circle
136π = 100π + πr²
πr² = 36π
r² = 36
r = 6
Therefore, Radius of the cone is 6 unit.