Quantities in physics that are meaningful need to correspond to some actual measurement one can do. Therefore if we want "time" to mean something of physical significance we need to fundamentally define it by some measurement. This measurement is the ticking of a clock, carried by some observer whom we'll call Finn. If you answered anything else in the last problem, you are putting extra, unwarranted, non-physical assumptions.
At this point, any other idea you have about what time should be is incorrect and gotten rid of.
This last point is important. One of the hardest things to do for physicists is to get rid of preconceptions, but we construct physical theories based upon what the world tells us, not the other way around. Nature doesn't respond when I wake up in the morning and say "I'd like a light gravity day." Not even if I say please.
Question 2: Consider some other observer, named Aaron, who is not co-located with Finn and is carrying his own clock. (Co-located is a fancy word for "standing on top of one another".) If we know the ticks of Finn's clock we can say which of the following about Aaron's clock?
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There is no reason why Aaron should be measuring the same time as Finn or ticking at the same rate because no relations between these two clocks have been given