Solutions of Benzene and Toluene Obey Raoult's Law

Multiple Choice

Solutions of benzene and toluene obey Raoult's law.The vapor pressures at 20°C are: benzene,76 torr;toluene,21 torr.
-If the mole fraction of benzene in a particular benzene-toluene solution is 0.64,what is the mole fraction of benzene in the vapor phase in equilibrium with that solution?

A) 0.24
B) 0.50
C) 0.64
D) 0.78
E) 0.87