Me with numbers 1 2 3 and 6 u need for today

Find the slope of a line given the following two points

For which pair of functions is (gof)(a)=|a|-2?

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.