Calculating time intervals involves converting days, hours, and minutes into a uniform unit. To determine the total time for 0 days, 720 hours, and 0 minutes in the past, start by converting the hours and minutes into equivalent days. There are 24 hours in a day, so 720 hours is equal to 30 days (720 hours ÷ 24 hours/day). Since there are 60 minutes in an hour, 0 minutes is equivalent to 0 days. Combining these, the total time elapsed is 30 days.