Rewrite the expression by using grouping symbols. y • 4 + y • z a. y • (4 + y) • z b. y (4 + z) c. 4(y + z) d. z(y • 4)

Will give the box plots below show the math scores of students in two different classes: class a 55 72 75 89 95 class b 55 70 75 94 100 based on the box plots, which statement is correct? a: the median score of class a is greater than the median score of class b. b: the lower quartile of class a is greater than the lower quartile of class b. c: the upper quartile of class a is greater than the upper quartile of class b. d: the maximum score of class a is greater than the maximum score of class b.