The best definition you can think of for confused

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

Which graph represents the equation y =4x

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?