A delivery truck travels between two cities, A and B, which are 150 kilometers apart. The truck travels at a constant speed of 60 kilometers per hour. If the truck leaves city A at 8:00 AM, what time will it reach city B? Additionally, if the truck has to make a return trip immediately after unloading, what will be the total travel time for the round trip including a 30-minute unloading time at city B? Let's think step by step and output the final answer within \boxed{}.
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