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The table below reports the mean and standard deviation for two tests: Test Mean Standard Deviation Biology 68 7 Economics 74 9 Tom scored 63 on the biology test and 68 on the economics tests. Which test did he perform WORSE on when compared to the average? Biology z-score = [ Select ] [ Select ] [ Select ] [ Select ] Economics z-score = [ Select ] [ Select ] [ Select ] [ Select ] Tom did worse on his [ Select ] test