The ultraviolet radiations from the sun cause reactions that produce

Which of the following statements about ozone is correct?

Ultraviolet radiation from sunlight causes the reaction that produces:

Which of the following is not one of the prime health risks associated with greater $UV$ radiations through the atmosphere due to depletion of stratospheric ozone?

How is the ozone hole formed? What is the Montreal Protocol? Explain.

The Montreal Protocol,which calls for appropriate action to protect the ozone layer from human activities,was passed in the year: