4.128 Roll a pair of dice two times. Consider rolling a pair of fair dice two times. Let A be the total on the up-faces for the first roll and let B be the total on the up-faces for the second roll. For each of the following pairs of events, tell whether they are disjoint, independent, or neither.

1. (a) A = {2 on the first roll}, B = {8 or more on the first roll}.

2. (b) A = {2 on the first roll}, B = {8 or more on the second roll}.

3. (c) A = {5 or less on the second roll}, B = {4 or less on the first roll}.

4. (d) A = {5 or less on the second roll}, B = {4 or less on the second roll}.