What’s the gcf of 56 and 90

Aregular hexagon rotates counterclockwise about its center. it turns through angles greater than 0° and less than or equal to 360°. at how many different angles will the hexagon map onto itself?

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

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