Each marble bag sold by Carmen's Marble Company contains 3 purple marbles for every 4 blue marbles. If a bag has 28 blue marbles, how many purple marbles does it contain?

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