Problem 21 (Plug-n-chug). You are taking your German shepherd for a walk in ReidPark when she decides to chase a Black-crowned Night-Heron by the pond. You pull back with a

force of T on her leash, which makes an angle of 0 with the horizontal. However,the dog is stronger than you are, and pulls you forward a distance of x. How much work do you do on the dog? \text { (a) } T x \cos \theta \text { (b) }-T x \cos \theta \text { (c) } T x \sin \theta \text { (d) }-T x \sin \theta \text { (e) None of these }