Three closed vessels A , B and C are at the same temperature T and contain gases which obey maxwellian distibution of velocities . Vessel A contains only $\;O_{2}\;$ . B only $\;N_{2}\;$ and C a mixture of equal quantities of $\;O_{2}\;$ and $\;N_{2}\;$ . If the average speed of $\;O_{2}\;$ molecules in vessel A is $\;V_{1}\;$ , that of $\;N_{2}\;$ molecules in vessel B is $\;V_{2}\;$ the average speed of the $\;O_{2}\;$ molecules in vessel C will be

Question

$(a)\;(V_{1}+\large\frac{V_{2}}{2})\qquad$$(b)\;V_{1}\qquad$$(c)\;\sqrt{V_{1}V_{2}}\qquad$$(d)\;\sqrt{\large\frac{3CT}{M}}$