Which rate describes a unit price? a. $0.01 for 12 seconds b. $0.25 for 5 minutes c. $1.00 for 4 hours d. $5.00 for 1 day

$ 5 for 1 day is a unit rate5/1...its when rate are expressed as a quantity of 1.

for example : $ 1 for 4 hrs...the unit rate for this would be : 1/4 = 0.25 per hr
and 0.25 for 5 minutes...the unit rate for this would be 0.25/5 = 0.05 per minutethe unit rate is per 1

A unit price is a price per 1 something.
It can be a price per 1 pencil, a price per 1 book, a price per 1 loaf of bread, etc.

Your choices are:
a. $0.01 for 12 seconds   ---> price per 12 seconds
b. $0.25 for 5 minutes   --->  price per 5 minutes
c. $1.00 for 4 hours   ---> price per 4 hours
d. $5.00 for 1 day   ---> price per 1 day

Only one choice is a price power 1 unit.
That is the unit price.