How is CO released into atmosphere?

Radioactive substances are released into atmosphere by

First O_(2) , was released into the atmosphere by

How is energy released in the cytoplasm

(A): The pH of normal rain is 5.6. (R) CO_2 present in atmosphere absorbed in moisture to give H^+ and HCO_(3)^(-)

Increase in atmospheric CO_(2)

A 50% increase of CO_2 level in atmosphere causes

How do you appreciate the role of molecules in the atmosphere for the blue colour of the sky ?