When you use the midpoint formula can you take either points as x ,y? why or why not ?

The answers are 20,30,80,180,960,890,1230,4560. on the first row

The question is kind of confusing. if it's asking how many variations of answers can you give. then do 4^5 for your answer.this would be something like the first question could be a and the 2nd c or first b next c etc. if you can, ask the teacher for a better confirmation of what it's asking. if i'm assuming correctly what it's asking, it's 625 different variations.