Bells are made of metal and not of wood because A. The thermal conductivity of metal is greater than that of wood B. The density of the metal is greater than that of wood C. The sound is not conducted by wood and metals are elastic D. Wood dampens vibrations while metals are elastic

What type of questions asked from the lesson of magnetic effect of electric current 

Wavelength of green light is

A) 400-450 nm

B) 500-550 nm

C) 660-720 nm

D) 720-800 nm

What is the difference between anaerobic & aerobic respiration? Name some organism that uses the aerobic mode of respiration?

What are the main components of our environment? Explain each of them briefly.

What are examples of hydrotropism plants?