Step-by-step explanation:
Answer:
Given :-
A closed cylindrical tank of radius 3.5 m and height 2 m is made from a sheet of metal.
To Find :-
How much sheet of metal is required.
Formula Used :-

where,
r = Radius
h = Height
Solution :-
Given :
Radius = 3.5 m
Height = 2 m
According to the question by using the formula we get,
⇒

⇒

⇒

⇒

➠

∴ 121 m² of sheet of metal is required.