71. Three containers of the same volume contain three different gases. The masses of the molecules are

m₁,m₂ and m₃ and the number of molecules in their respective containers are N₁,N₂  and N₃ . The gas pressure in the containers are P₁,P₂  and P₃ respectively. All the gases are now mixed and put in one of the containers. The pressure P of mixture will be

(a)  P< ( P₁ + P₂ + P₃ )                             (b)  P=( P₁ + P₂ + P₃ )/3

(c) P=( P₁ + P₂ + P₃ )                               (d) P>( P₁ + P₂ + P₃

Answer-c