Answer: 144
============================================
Step-by-step explanation:
This is something you can do though trial and error. Start at 8 and work your way up squaring each whole number.
8^2 = 64 is a multiple of 8, 4 and 2, but not a multiple of 6
9^2 = 81 is a multiple of neither 2,4,6,8
10^2 = 100 is a multiple of 2 and 4 but nothing else in the list
11^2 = 121 is a multiple of neither 2,4,6,8
12^2 = 144 is a multiple of all four values 2,4,6,8 as each division results in a whole number, as shown below:
144/2 = 72
144/4 = 36
144/6 = 24
144/8 = 18
Those four computations show how 144 is a multiple of 2,4,6, and 8.