Simplify. Write "undefined" for expressions that are undefined. I don't understand it, can someone help?

Aswim teacher sells lesson packages. the best deal has the highest ratio of lessons to total cost.swim lesson packagesnumber of lessons total cost$10$4010 1 $8015$80which package is the best deal? l lesson for $105 lessons for $4010 lessons for $8015 lessons for $80mark this and returnsave and exit

In the xy-plane, if the parabola with equation passes through the point (-1, -1), which of the following must be true?

Layla answer 21 of the 25 questions on his history test correctly.what decimal represents the fraction of problem he answer incorrectly.