Please give me the correct answer.

Given the function f(x) = log base 4(x+8) , find the value of f^-1(2)

Svetlana's hair is 4 4 centimeters ( cm cm) long. her hair grows 1 . 5 cm 1.5cm per month. svetlana wants her hair to be less than 1 6 cm 16cm long. write an inequality to determine the number of months, m m, svetlana can allow her hair to grow so that it is less than 1 6 cm 16cm long.

Complete the solution of the equation. find the value of y when x equals to 6 4x+y=20