Answer:
Explanation:
The surface area of the cone would be the sum of the lateral surface area of the cone and the total surface area of the cylinder (one side open)
Lateral surface area of cone = πrl
Diameter of cone = 8 in
Radius, r = 8/2 = 4 in
height of cone = 3 in
To find the slant height, l, we would apply Pythagoras theorem. Thus
l² = 4² + 3² = 25
l = √25 = 5 in
Lateral surface area of cone = π × 4 × 5 = 20π
Formula for total surface area of cylinder required(one side open) is
2πrh + πr²
From the information given,
Height of cylinder, h = 5 in
Radius of cylinder = radius of cone = 4 in
Total surface area = (2 × π × 4 × 5) + (π × 4²) = 40π + 16 π = 56π
The surface area of the rocket = 20π + 56π = 76π sq. in