Find the roots of the function.
ƒ(x) = x^2 + 81

x = -81i, 81i
x = -81, 81
x = -9, 9
x = -9i, 9i

Kilgore trout creates a new scale to diagnose depression. however, his scale only assesses one symptom of depression while ignoring others. which of the following is his new scale most likely lacking? a) test-retest reliability b) discriminant validity c) criterion validity d) alternate-forms reliability e) content validity f) none of the above