4- Two organic solvents (A and B) form an ideal solution when they mixed at 25 C. The vapor pressures of A and B solvents at 25 C are 500 and 180 mmHg, respectively. By mixing 30 mL of A (c=0.64 g/mL) with 48 mL B (d=0.67 g/mL), an ideal solution is prepared. a- What is the vapor pressure of resulting ideal solution? b- What is the composition by mole fraction of A in the vapor that is in equilibrium with this solution? (M., of A= 72.15 g/mol; My of B= 86.17 g/mol)