Mensuration Practice Test 2

Radius of the semicircle will be the slant height of the cone = 6 cm.
Circumference of Semicircle will be circumference of base of cone = πr = $\frac{22}{7}\times 6$
So, LA of cone = πrl = $\frac{22}{7}\times 6\times 3$ = $56.7\mathit{c}{\mathit{m}}^2$