Question 380938
a. The sample space : {{n,d,q}, {n,d,f}, {n,q,f}, {d,q,f}}, there are four sample points.  Note that for each sample point order doesn't matter.
b. 3/4.  {{n,d,f}, {n,q,f}, {d,q,f}}
c. 3/4.  {{n,d,f}, {n,q,f}, {d,q,f}}