Seeds fall on a landscape that contains 70% barren rock. The remainder of the landscape is suitable habitat for the seeds to germinate. Assume that the location where a seed falls in this landscape is random with respect to the site’s suitability for germination.

a. What is the probability that a single seed lands on a suitable site for germination?

b. If two seeds fall independently, what is the probability that both fall on suitable habitats?

c. Suppose that three seeds fall randomly and independently onto this landscape. Use a probability tree to find the probability that exactly two of these three seeds land on suitable habitat.