Affected by the pandemic of COVID-19, airlines have ceased operations in majority of the routes and grounded a large number of airplanes. Please use graphs to illustrate why airlines react in this way. (Hint: Please explain how demand change after the outbreak of COVID-19 affects airlines' revenue and costs.)

On a particular day before departure, two seats are still unsold on the flight departing at the peak period, but many seats are available on the off-peak flight. There are three potential passengers. Their WTP for the peak flight and off-peak flight are listed below.

Passenger

WTP (off-peak)

WTP (peak)