5.16 Three Coins The sample shows the possible sequences for flipping three fair coins or flipping one coin three times, where H stands for heads and T stands for tails. HHH HHT HTT TTT HTH THT THH TTH Assume that all of the 8 outcomes are equally likely. Find the probability of having exactly the following numbers of heads out of the 3 coins: (a) exactly 0 heads, (b) exactly 1 head, (c) exactly 2 heads, (d) exactly 3 heads. (e) What do the four probabilities add up to and why