Answer:
<h2>See the explanation.</h2>Step-by-step explanation:
(a)
7 persons will show up for sure, hence there is not any kind of probability here.
The other 5 persons have 50% chance to show up.
The flight will be overbooked, if either 4 will come or 5 will come.
From the total 5 persons, 4 can be chosen in ways.
The probability that any four among the 5 will come is .
The probability that all of the 5 passengers will come is .
Hence, the required probability is .
(b)
The probability that there will be exactly 10 passengers on the flight is .
The probability that there will be no empty seats in the plane is .
Hence, probability of having empty seats is .