Two unfair coins are tossed with the probability of a tail equal to 0.25. Calculate the probability ofgetting:(a) No heads.(b) Exactly one head.(c) At least one head.

(a) No heads: This means getting tails on both coins. The probability of getting a tail on one coin is 0.25. Since the coins are independent, the probability of getting tails on both is (0.25)*(0.25) = 0.0625.

(b) Exactly one head: This means getting a head on one coin and a tail on the other. The probability of getting a head is 1 - 0.25 = 0.75. So the probability of getting a head on one coin and a tail on the other is (0.75)(0.25). But this can happen in two ways (head on first coin and tail on second, or tail on first coin and head on second), so we multiply by 2. The total probability is 2(0.75)*(0.25) = 0.375.

(c) At least one head: This means getting a head on at least one of the coins. The easiest way to calculate this is to find the probability of the opposite event (getting tails on both coins, which we calculated in part (a) as 0.0625), and subtract it from 1. So the probability of getting at least one head is 1 - 0.0625 = 0.9375.