If a and b are two natural numbers such that a3 = b, then b is called the cube of a.
If the units digit of a3 is b, then the cubes of all numbers ending with a will have their units digit as b.

The cubes of all numbers that end in 2 have 8 as the units digit. The cubes of all numbers that end in 3 have 7as the units digit.
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