In most state and local courts, 12 jurors and 2 alternates are chosen from a pool of 30 prospective jurors. The order of the alternates is specified. If a juror is unable to serve, then the first alternate will replace that juror. The second alternate will be called on if another juror is dismissed.
a. In how many ways can 12 jurors and first and second alternates be chosen from 30 people?
b. In federal court cases, 12 jurors and 4 alternates are usually selected from a pool of 64 prospective jurors. In how many ways can this be done?