Wednesday, 4:00 AM.
12 noon Wednesday.
24 hours / day 72 / 24 = 3 days 4 days is greater than 72 hours
Seventy-two hours from Sunday night at 12 pm would be Wednesday night at 12 pm. To calculate this, we add 72 hours to the initial time. Sunday night at 12 pm is essentially Monday at 12 am, so adding 72 hours takes us to Wednesday at 12 am. Finally, adding another 12 hours brings us to Wednesday night at 12 pm.
4:45 pm on Wednesday
3 days are in 72 hours.