The common gracklc is a species of robin-sized blackbirds that are fairly common over most of the United States. Suppose that long tails (L) were dominant to short tails (1) in these birds. A female short-
tailed grackle mates with a male long-tailed grackle that had one parent with a long tail and one parent
with a short tail. What is the tail length probability of thcir offspring?