Trucks that travel on U.S. highways have to stop at various locations to be weighed and inspected for safe brakes and light systems. Of these trucks, 77% are on interstate commerce business while 23% are intrastate. Of the intrastate trucks, 3.1% are flagged for safety defects compared to 0.7% of those that are on interstate business.
a. Calculate the probability that a randomly chosen truck is an interstate truck and is not flagged for a safety violation.

b. What is the probability that a randomly chosen truck does not have a safety defect?

c. If two trucks are chosen randomly, determine the probability that only one of the two does not have a safety defect.