A street cleaning crew works only Monday to Friday, and only during the day. It takes the crew an entire morning or an entire afternoon to clean a street. During one week the crew cleaned exactly eight streets—First, Second, Third, Fourth, Fifth, Sixth, Seventh, and Eighth streets. The following is known about the crew’s schedule for the week:
The crew cleaned no street on Friday morning.
The crew cleaned no street on Wednesday afternoon.
It cleaned Fourth Street on Tuesday morning.
It cleaned Seventh Street on Thursday morning.
It cleaned Fourth Street before Sixth Street and after Eighth Street.
It cleaned Second, Fifth, and Eighth streets on afternoons.
What is the maximum possible number of streets any one of which could be the one the crew cleaned on Friday afternoon?