31 Lungs are part of the

Respiratory system

32 Kidney are part of the

Excretory system

33 Uranium is a

Soft grey metal

34 The commercial importance of Uranium is

Its explosive property

35 Silkworm is a

Caterpillar

36 Silk is obtained from

Silkworm

37 What is a quarry?

An open pit dug in the ground to take out the rock and sand with ease

38 The planet between Earth and Mercury is

Venus

39 How many planets of our Solar System have no satellites?

Two (3)

40 The Two planets of our Solar System that do not have satellites are

Mercury and Venus