Is there a way to convert a time interval to show coverage for 15 min
increments?

For example:
9am -11am would look like this:
TIME SHIFTS
A1: 9 - 9:15 A2: 1
B1: 9:15-9:30 B2: 1
C1: 9:30-9:45 C2:1
D1: 9:45-10 D2:1
E1: 10:10:15 E2:1
F1: 10:15-10:30 F2:1
G1: 10:30-10:45 G2:1
H1: 10:45-11 H2:1

I am trying to break down shift coverage into 15 minute slots. I'd like to
be able to enter the coverage time and then have the spreadsheet show how
many people would work on that 15 min spot.

Thanks in advance.