The coordinates of three of the vertices of parallelogram abcd are a(2, 0), b(4, 3), c(3, 1). how many possibilities are there for the position of the fourth vertex? what are coordinates of the fourth vertex?

Liz is shipping a package to her friend.the maximum weight of a medium flat-rate box is 20 pounds,including the box which weighs 6 ounces.write and solve an inequality to describe the possible weight ,w, of the contents that liz will ship to her friend if she must use a medium flat-rate box.