In one mid-western city, the government has 14 repossessed houses, which are evaluated to be worth about the same. Ten of the houses are on the north side of town and the rest are on the west side. A local contractor submitted a bid to purchase four of the houses. Which houses the contractor will get is subject to a random draw.

a. What is the probability that all four houses selected for the contractor will be on the north side of town?

b. What is the probability that all four houses selected for the contractor will be on the west side of town?

c. What is the probability that half of the houses selected for the contractor will be on the west side and half on the north side of town?