Of the 220 tickets available for a school play,45% have been sold. What is the number of tickets that have sold?(pls help due very soon!)

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