Question

1. find the surface area of the cone in terms of π. (there is a cone diagram with diameter 12 cm and slant height 18 cm)

Explanation:

Step1: Find radius of base

Radius $r = \frac{12}{2} = 6$ cm

Step2: Calculate lateral surface area

Lateral surface area = $πrl = π×6×18 = 108π$ cm²

Step3: Calculate base area

Base area = $πr² = π×6² = 36π$ cm²

Step4: Sum to get total surface area

Total surface area = $108π + 36π = 144π$ cm²

Answer:

144π cm²