Plz me, and explain how you did it, because they are for a 5th grader. : )

Apublic library wants to place 4 magazines and 9 books on each display shelf. the expressions 4s +9s represents the total number of items that will be displayed on s shelves. simplify this expression

The base of a triangle is 8 1 3 meters and the height of the triangle is the fourth root of 16 meters meters. what is the area of the triangle?

What are the exclude value of mn+3m