What is the study of population called?

Which of the following metals is used in spacecraft to tolerate high temperatures?

The metal present in insulin is

Elements of d-block are called–

Which one among the following nontoxic gases helps in formation of enzymes which ripen fruit?

What would be the time period of a pendulum, when taken to the Moon?  

If the velocity of a body is doubled its kinetic energy

One horse power is equal to