Answer:
Store D
Explanation:
Store A:
25 dollars for 45 minutes, that means .5555 dollars per minute
Store B:
30 dollars for 60 minutes (1 hour), that means .5 dollars per minute
Store C:
45 dollars for 90 minutes (1.5 hours), that means .5 dollars per minute
Store D:
80 dollars for 180 minutes (three 1 hour lessons), that means .444 per minute