The infrastructure of a large American city is deteriorating. Water line breaks occur randomly and independently of one another. On average, there are 30 breaks per 100 kilometers of water line (carrying water to homes and businesses) in the city. In comparison, There are only 15 breaks per 100 kilometers of water line outside the city.
a. What is the probability of 35 or more breaks in a 100 kilometer stretch of water line in the city?
b. What is the probability of 12 or fewer breaks in a 100 kilometer stretch of water line outside the city?