Is a number a multiple of 4 of its last two digits are divisible by 4?

Yes

If a numbers last two digits (assuming that it has at least two) is a multiple of 4, the whole number is also a multiple of 4.

If the last two digits are 00 (assuming in this case it has at least three digits), the number is also a multiple of 4. For example, 100 and 200 are multiples of 4.