Complete the following by selecting the correct option from the choices given : The metal which does not react with water or dilute H_2SO_4 but reacts with concentrated H_2SO_4 is ________ .(Al//Cu//Zn//Fe)

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?