Length of the roof = 44 m

Breadth of the roof = 20 m

Diameter of the cylindrical tank = 4 m

Radius of the cylindrical tank = 2 m

Height of the cylindrical tank = 3.5 m

Volume of roof = l x b x h
= 44X20 X h
volume of cylinder = x2x2x

Height of roof = height of rainfall
And
Volume of water on roof = Volume of Water in cylindrical tank
44X 20 X h = × 2 x 2 x
44 X 20 X h = 22 × 2 × 2 ×

880 × h = 44
h =
h = .05 m
h = 5 cm