I need help on these two questions please.

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.

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c

Solve for x and select the correct answer