A perfect square number is a number that can be expressed as the product of an integer by itself
or as the second exponent of an integer
for example 25 is a perfect square because 5*5=25
then
12 is not a perfect square
84 is not a perfect square
144 = 12*12 then 144 is a perfect square
24 is not a perfect square
4= 2*2 then 4 is a perfect square
64 =8*8 then 64 is a perfect square
49=7*7 then 49 is a perfect square
then from all numbers in the list
144
4
64
49
are perfect squares
