Donna has a checking account that charges $0.15 for each check written and a monthly service charge of $9.75. Write a

formula that Donna can use each month to find the fees she will

be charged. Identify any variable you use in the formula.

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

answer: 1, 3 and 5 are correct

step-by-step explanation:

600,000,000,000, or 6e14

step-by-step explanation: