$1$) `A = 2^2 - 6.2 + 9 = 4 - 12 + 9 = 1`
$2$) `B = (-5)^2 - 10.5 + 25 = (5+5)^2 = 100`
$3$) `C = 87^2 - 13^2 = (87-13).(87+13) = 74.100 = 7400`
$4$) `D = 97^3 + 9.97^2 + 27.97 + 27 = (97+3)^3= 100^3 = 1000000`
$5$) `E = 101^3 - 3.101^2 + 3.101 - 1 = (101-1)^3 = 100^3 = 1000000`
$6$) `F = 2^3 - 6.2^2 + 12.6 -8 = (2-2)^3 = 0`
$7$)`G=103^2 - 6.103 + 10 = (x-3)^2 + 1 = 100^2 + 1 = 10001`