4 At a certain airport 20\% of people take longer than an hour to check in. A new computer system is installed, and it is claimed that this will reduce the time to check in. It is decided to accept the claim if, from a random sample of 22 people, the number taking longer than an hour to check in is either 0 or 1 .

1. Calculate the significance level of the test.
2. State the probability that a Type I error occurs.
3. Calculate the probability that a Type II error occurs if the probability that a person takes longer than an hour to check in is now 0.09 .