A blue litmus paper was first dipped in dilute HCl and then in dilute NaOH solution. It was observed that the colour of litmus paper_______ A.Changes to red B.Firstly changed to red and then to blue C.Changed blue to colorless D.Remained blue in both the solutions

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?