Anybody know the answer to this?

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

If 2(a^2+b^2)=(a+b)^2 then, > a+b=0, > ab=0, > a=b, > 2a=b

Polygon abcd is a parallelogram, and m? abc = 127°. the length of is 10 units, and the length of is 5 units. the perimeter of the parallelogram is units, and m? bcd is °