125.7cm²
Step-by-step explanation:
Given parameters:
Slant height, L = 6cm
Base radius  = 4cm
Unknown:
Total surface area = ?
Solution:
To find the total surface area, we use the expression;
   Surface area = r² + rL Â
Now insert the parameters and solve
  Surface area = r(r + L )
  Surface area  =  x 4 (4 + 6) = 3.142 x 4 x 10  = 125.7cm²