As we know that the leaves of plants are waterproof due to cuticle. On the same way, take some pieces of paper of leaf size and make them waterproof. After completion, put half of these
paper pieces in cold water and half in hot water. Do all the pieces of paper remains waterproof?
Explain your observations and results with justifications

No.

Explanation:

No, all the pieces of paper did not remains waterproof because expansion of paper occur due to high temperature of hot water. We know that materials expand when they experience high temperature and contract when they observe cold temperature. So the pieces of paper remains waterproof which were put in cold water while those were not waterproof if they are put in hot water.

your answer is "the 1950's"