Which expression is equivalent to 30(1/2x - 2) plus 40(3/4y-4)

Olga used 100 ounces of flour to make 225 muffins. how many ounces of flour will be used to make 300 muffins?

If chord ab is congruent to chord cd, then what must be true about ef and eg?

The median am of triangle ∆abc is half the length of the side towards which it is drawn, bc . prove that triangle ∆abc is a right triangle, and find angle mac and abm