URGENT: Please help as soon as possible, this is a precalculus question I need help on

Which of the following is not a subset of {1,2,3}?

What is the solution to the division problem below x3+x2-11x+4/x+4

Luke started a weight-loss program. the first week, he lost x pounds. the second week, he lost pounds less than times the pounds he lost the first week. the third week, he lost 1 pound more than of the pounds he lost the first week. liam started a weight-loss program when luke did. the first week, he lost 1 pound less than times the pounds luke lost the first week. the second week, he lost 4 pounds less than times the pounds luke lost the first week. the third week, he lost pound more than times the pounds luke lost the first week.