Find the value of x. (and the rest)

Elizabeth claims that the fourth root of 2 can be expressed as 2^m since (2^m)^n = 2. find the values of m and n for the case where elizabeth's claim is true.

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?