Question

plzzzzzz answer its so argent..

Answer 1

total surface area will be the surface area of big cylinder

Answer 2

Hey!

Inner radius (r1) = 4/2 = 2 cm
Outer radius (r2) = 4.4/2 = 2.2 cm
Height = Length = 77 cm
(i) CSA of inner surface of pipe:
= 2πr1h


= (2 *22/7 * 2 * 77) cm2
= 968 cm2
(ii) CSA of outer surface of pipe
= 2πr2h
= (2 * 22/7 * 2.2 * 77) cm2
= (22 * 22 * 2.2) cm2
= 1064.8 cm2
(iii) TSA = Inner CSA + Outer CSA + Area of both circular ends of pipe
= 2πr1h + 2πr2h + 2π (r22 – r12)
= [968 + 1064.8 + 2π {(2.2)2 - (2)2}] cm2
= (2032.8 + 2 * 22/7 * 0.84) cm2
= (2032.8 + 5.28) cm2
= 2038.08 cm2
Therefore, the total surface area of the cylindrical pipe is 2038.08 cm2

HOPE THIS WILL HELP YOU