According to the present estimates,what percentage of the world's petroleum will be exhausted by the year $2025$ (in $\%$)?

What is the full form of $GNP$?

Reserpine, an alkaloid or drug extracted from the roots of which of the following plants, cures mental disorders and reduces or checks blood pressure?

Camphor is obtained from which part of the following?

Which of the following plants is not related to the family $Leguminosae$ (Fabaceae)?

Which of the following is a gift of the New World to the Old World?