Which of the following is NOT true for the function $f(x)=x^2-4x, x\in [0, 4]$ ?

f is decreasing in (0, 2) x=2 is the local minima of f. $f(x)= 3$ has two positive solutions $f(x) = - 2$ has two positive solutions.

$f(x)= 3$ has two positive solutions