Which of the following are valid hexadecimal numbers? How do you know?

ace f32e BABE BLEED 4567

ace f32e BABE 4567

Explanation:

A hexadecimal number is a base 16 number and consists of digits [0,1,2,3,4,5,6,7,8,9] and characters [A, B, C, D, E, F].

ace is hexadecimal as it consists of characters a, c, e

f32e is hexadecimal as it consists of characters f, e and digits 3,2

BABE is hexadecimal as it consists of characters B, A, E.

BLEED is not hexadecimal as it contains character L which is invalid.

4567 is hexadecimal as it contains digits 4,5,6,7.