Which relation is a function? A. (4-2), (5,-3), (6,-2), (7,-3) B. (3,10), (2,20), (3,30), (4,40) C. (-5,2), (-5,3), (-10,4), (-10,5) D. (10,15), (20,25), (8,30), (20,35)

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?