A grocery store chain is comparing the sales of two brands of frozen cakes. The bakery manager randomly selected sales from 10 days to compare the two brands. The monthly sales data for each brand of cake is in the back-to-back stem plot below. Which statement(s) are true?

I -- on average, Brand A sells more cakes each month ;

II -- on average, Brand B sells more cakes each month ;

III -- on average, each brand sells the same number of cakes each month ;

IV -- the averages are the same, but Brand B sells more cakes each month