7. [v hard] There are N passengers boarding a full flight. They have assigned seats but they have all lost their boarding passes, so they choose to sit in random seats. [Fa17 Final] a. What is the expected number of passengers who sit in their assigned seats? i. 1 b. What is the probability that i passengers sit in their assigned seats? n-i i. E (- 1)'n choose (i + )-th)!)by Inclusion-Exclusion 1=0