Help me with these problems please

What is the approximate total length of iron edging needed to create the square frame and the two diagonals?

The multiplication property of zero states that the product of any number and 0 is 0. what must be true about either a or b to make ab=0

Which equation shows the variable terms isolated on one side and the constant terms isolated on the other side for the equation -1/2x+3=4-1/4x? a. -1/4x=1 b. -3/4x=1 c. 7=1/4x d. 7=3/4x