How is the relative humidity expressed?

Some tips and related energy conversions are given below?
(i) Electrical Generator - Electrical from Mechanical
(ii) Electric motor - electro-to-mechanical
(iii) Diesel engine - electric from light
(iv) Solar cells - chemical to mechanical
Which of the above pairs is related to it?

Cadmium pollution is associated with ____?                              

Which date is known as ' Diabetes Day? 

From whom do teeth and bones gain strength and firmness?

An element that does not occur in nature but can be produced artificially is 

This organelle of the human body is known as the ‘powerhouse of the cell’. Name it from the given options.

Is there concentration in the eye?