(a)[2]
How many different seating arrangements are possible for the $12$ passengers? Give your answer correct to $3$ significant figures.
(b)[4]
The $12$ passengers are made up of $2$ married couples (Mr and Mrs Lin and Mr and Mrs Brown), $5$ students and $3$ business people. The $3$ business people are seated in the front row. Each of the $5$ students sits in a window seat. Mr and Mrs Lin sit in the same row on the same side of the aisle. Mr and Mrs Brown sit in a different row on the same side of the aisle. How many possible seating arrangements are there?
(c)[4]
If, instead, the $12$ passengers are seated at random, find the probability that Mrs Lin sits directly behind a student and Mrs Brown sits in the front row.