students of a school are standing in rows and columns in their playground for a drill practice. a, b, c and d are the positions of four students as shown in the figure. (a) what are the coordinates of a and b respectively? (b) what are the coordinates of c and d respectively? (c) what is the distance between b and d? (d) what is the distance between a and c? (e) what are the coordinates of the point of intersection of ac and b​