**ANSWER TO DIAGONAL THINKING:**

185 Meters.

Chuck walked 112 meters from **A** to **B**.
Heidi walked 73 meters from **D** to **
C**. The radius of the field is thus 112+73 = 185 meters. The diagonals of a
rectangle are equal. The distance along **CA** is the same as the distance
along **EB,** which of course is the radius of the quarter circle.