Question 1180129
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A driver leaves his house at 7:00 a.m. and arrives at his work at 8:00 a.m. 
The maximum speed at which it travels is 45 miles per hour. 
If the speed is time dependent, describe the reasonable domain.
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In this problem, the meaning is hidden behind the words.


It would be naturally to ask to estimate the distance,
but then the problem would be too simple.



But if you don't bother with words, then the natural answer is:

     the distance is not more than 1*45 = 45 miles.


Here factor "1" represents the travel time of 1 hour, 
which is given in the problem as a constant value.
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Solved and explained.