Answer:
(d) 480 minutes, and 6 hours
Explanation:
An hour is 60 minutes, so you have ...
3 hours = 180 minutes . . . . . adding 10 minutes gives 190 minutes
4 hours = 240 minutes
5 hours = 300 minutes . . . . . adding 50 minutes gives 350 minutes
6 hours = 360 minutes
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480 minutes is 8 hours, not 6 hours.
480 min ≠ 6 h