An important evidence in favour of organic evolution is the occurrence of

The electrons which take part in order to exhibit variable oxidation states by transition metals are

$A$ river is flowing from east to west at a speed of $5\ m/min$. $A$ man on the south bank of the river,capable of swimming $10\ m/min$ in still water,wants to swim across the river in the shortest time. He should swim:

Which of the following elements is a constituent of biotin?

The intensity of the magnetic induction field at the centre of a single turn circular coil of radius $5 ~cm$ carrying a current of $0.9 ~A$ is:

The correct formula of diammine dichlorodicyanochromate$(III)$ ion is