Which of the following is the strongest reducing agent?

Quinine,used for the treatment of malarial fever,is extracted from:

Two bodies of mass $4 ~kg$ and $5 ~kg$ are moving along east and north directions with velocities $5 ~m/s$ and $3 ~m/s$ respectively. The magnitude of the velocity of the centre of mass of the system is

Which pigment is present in all algae?

What is obtained by the reaction of $HCOOH$ with concentrated $H_2SO_4$?

At a certain place,the horizontal component of Earth's magnetic field is $\sqrt{3}$ times the vertical component. The angle of dip at that place is....$^o$