By using a computer algorithm, an investigator can assign members of twin pairs at random to an intervention condition in a clinical trial. Assume that each twin pair consists of dizygotic twins (one male and one female). The probability of assigning one member of the pair to the intervention condition is 50%. Among the first four pairs, what is the probability of assigning to the intervention condition: 1) zero females, 2) one female, 3) two females, 4) three females, 4) four females?