Flipping an image so that the coordinate change from XY 2Y axis called reflecting over the line

Answer these questions showing your work plz

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?

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).