Two heating elements of resistance R1 and R2 when operated at a constant supply of voltage, V, consume powers P2 and P2 respectively

Two heating elements of resistance Rj and R2 when operated at a constant supply of voltage, V, consume powers P2 and P2 respectively. Deduce the expressions for the power of their combination when they are, in turn, connected in (i) series and (ii) parallel across the same voltage supply.