b) (m^6)^-2/3
c) (3x^-4y^5)/((2x^3y^-7))^-2
D) is the correct answer because in this description it doesn't say that any of the students dislike a type of ice cream, just that they don't prefer it.
a. James is 3 years old; Henry is 4 years old.
b. Henry is 4 years old; James is 3 years old.
c. James is 2 years old; Henry is 8 years old.
d. James is 8 years old; Henry is 8 years old.