Question

an iron pipe 20 cm long has exterior diameter 25 cm and thickness 1 cm find the SA of the pipe​

Answer 1

Step-by-step explanation:

The given

a pipe length=20cm. and exterio diameter is = 25cm

pipe is 1 cm thick

Now. inner diameter = 25-2

inner (d) = 23

inner radius = 23/2

curve surface area = 2×pie ×r×h

2×22/7×23/2×20

22/7× 23×20

1445.71answer