How many hours from 730 to 615?

From 7:30am to 6:15pm is 10 hours and 45 minutes.

From 7:30pm to 6:15am is 10 hours and 45 minutes.

From 7:30pm to 6:15pm is 22 hours and 45 minutes.

From 7:30am to 6:15am is 22 hours and 45 minutes.