The element californium belongs to the family

The formula of azurite is

For a chemical reaction,$A + 2B \to C + D,$ the rate of reaction increases $3$ times when the concentration of $A$ only is increased $9$ times. While when the concentration of $B$ only is increased $2$ times,the rate of reaction also increases $2$ times. The order of this reaction is:

The materials having negative magnetic susceptibility are

If the charge on the capacitor is increased by $2 \ C$,the energy stored in it increases by $21 \%$. The total original charge on the capacitor is: (in $C$)

Find the magnetic field at point $P$ in the given diagram.