Enter the amplitude of the function.

f(x)=5cosx

?

#12 find the value of x. #13 find the value of the variable.

Which of the following represents the zeros of f(x) = 6x3 − 31x2 + 4x + 5? −5, one third , one half 5, − one third , one half 5, one third , − one half 5, one third , one half

I'll give brainliest if you answer right : )