When r, P and M represent rate of diffusion, pressure and molecular mass, respectively, then the ratio of the rates of diffusion (r_A / r_B ) of two gases A and B, is given as :
a) \[\left(P_{A}\diagup P_{B}\right)\left(M_{B}\diagup M_{A}\right)^{1\diagup 2}\]
b) \[\left(P_{A}\diagup P_{B}\right)^{1\diagup 2} \left(M_{A}\diagup M_{B}\right)\]
c) \[\left(P_{A}\diagup P_{B}\right) \left(M_{A}\diagup M_{B}\right)^{1\diagup 2}\]
d) \[\left(P_{A}\diagup P_{B}\right)^{1\diagup 2} \left(M_{B}\diagup M_{A}\right)\]

Answer: a
Explanation: