If a term in a polynomial only has a number part, it’s called a term.

Constant.

Step-by-step explanation:

If there is only a number and no variables attached, it is a constant term, which means the term will always stay the same, and will not change.

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So,

All we have to do is multiply the amount of water Andy carried by the fractional amount he drank.

1/2 * 2/3

This is pretty simple.  To halve TWO-thirds, just halve the numerator, since it's such a nice number.

Presto.  Half of two is one.

Therefore, 
1/2 * 2/3 = 1/3

Andy drank 1/3 gallons of water on his hike.  That's 5 1/3 cups of water.  I would estimate his hike to be about 3 miles.  Easy peasy.