Which study appears to look for an association between two variables without actively manipulating either one? what are those variables

Answer these questions showing your work plz

Identify the converse of the following conditional: if a point is in the first quadrant, then its coordinates are positive. if the coordinates of a point are not positive, then the point is not in the first quadrant. if the coordinates of a point are positive, then the point is in the first quadrant. if a point is in the first quadrant, then its coordinates are positive. if a point is not in the first quadrant, then the coordinates of the point are not positive.

Which expression gives you the distance between the points (5,1)and(9,-6)