The water level in a draining reservoir is changing such that the depth of water decreases by 7.5% per hour. If the water starts at a
depth of 45 feet, then which of the following functions properly
models the depth, d, as a function of time, t, in hours since it started
draining?
(1) d = 45(.075)'
(2) d = 45(.925)'
(3) d = 45(7.5)'
(4) d = 45(92.5)'

please answer fast, it’s for a timed test!!!