Write a quintic polynomial using only the variable X that has a leading coefficient of 19

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

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?