Question

Answer this........​

Answer 1

Answer:

Given: The length of entire solid = 30 cm

Diameter of cylinder and cone = 10.5 cm, r = 5.25 cm

Length of cylinder, H = 14 cm

Length of 2 cones = Length of entire solid - Length of cylinder = 30 - 14 = 16 cm

Length of each cones = 16 ÷ 2 = 8 cm

Height of the cone, h = 8 cm.

Surface area = ?

Formula: Total surface area of the cylinder = 2πRH + 2πrl

Substituting the values, we get the surface area value as

Surface area = 2 x π x 5.25 x 14 + 2 x π x 5.25 x 8

= 2π(5.25 x 14 + 5.25 x 8)

= 2π(73.5 + 42)

= 2π(115.5)

= 2\times\frac{22}{7}\times 115.52×722×115.5

= 2 x 22 x 16.5

= 726 cm²

The surface area is 726 cm².