Which is the greatest among `(81)^(18), (243)^(15), (27)^(21)` and `(9)^(38)` ?

Which is the greatest among (3)^(198), (27)^(64), (9)^(100) and (81)^(49) ?

Which is the greatest among (9)^6, (27)^5, (81)^4 , and (243)^2 ?

Which is the least among (3)^25, (9)^12, (27)^3 , and (81)^2 ?

Which is the greatest among the following ? (sqrt(3))^30, (sqrt(27))^4, (sqrt(81))^8, and (3sqrt(9))^12

The greatest common divisor (GCD) of 18 and 27 is

What is the greatest four digit number which when divided by 10, 15, 21 and 28 leaves remainders 4, 9, 15 and 22, respectively?