Square Root and Cube Root - General Questions

What is the least number that must be subtracted from 1102 to make it a perfect square?

What is the least number that must be subtracted from 8661 to make it a perfect square?

√144 × √9 + √1296 = ?

What is the least number that must be subtracted from 3384 to make it a perfect square?

√4 × √121 + √484 = ?