P and Q are ideal gases which do not reach with each other.  The mass of one mole of P is four times that of Q.  At STP, which of the following are true

The rate of diffusion of P is 4 times less than that of Q

The average K.E of molecules of P is equal to that of Q

On mixing $1d{m}^3$ of P with $1d{m}^3$  of Q the partial pressure of each gas in the mixture will be 0.5 atm 

The mass of  $1d{m}^3$ of P is four times that of $1d{m}^3$ of Q