An equimolar ideal liquid mixture of A ($P^0=90$ kPa) and B ($P^0=30$ kPa) is in equilibrium with its vapour. The vapour is condensed completely and the condensate is allowed to reach equilibrium with its own vapour at the same temperature. Which statements are correct?

1. AThe partial pressure of B above the original mixture is 30 kPa.
2. BThe mole fraction of A in the vapour above the condensate is 0.90.
3. CThe total vapour pressure above the original mixture is 60 kPa.
4. DThe mole fraction of A in the first vapour is 0.75.