1. The problem is to calculate the time difference between 2pm and 6:30pm. 2. We use the formula for time difference: $$\text{Time difference} = \text{End time} - \text{Start time}$$ 3. Convert the times to a 24-hour format or decimal hours for easier calculation: 2pm is 14:00 hours, and 6:30pm is 18:30 hours. 4. Calculate the difference: $$18.5 - 14 = 4.5$$ hours. 5. Therefore, the time difference from 2pm to 6:30pm is 4.5 hours. 6. This means you should substitute 4.5 hours in any related calculations involving this time interval.