Q1:

2^4 equally possible outcomes, out of which combinations of two in four is 4c2
4c2/2^4=3/8

Q2:

2 or 3 makes a majority out of 3 and one does for a minority, so if we assume that the minority is favourable and subtract its probability from 1 we have the probability for the majority. Each of the critics could be the favouring critic while the others are not, thus:
1 - (3/5*3/7*3/5 + 2/5*4/7*3/5 + 2/5*3/7*2/5)=0.64