MATH PUZZLE: Can you replace...

In light of the rising frequency of human - grizzly bear conflicts, the Alaska Department of Fish and Game is advising hikers, hunters, and fishermen to take extra precautions and keep alert of bears while in the field. They advise that outdoorsmen wear noisy little bells on their clothing so as not to startle bears that aren't expecting them. They also advise outdoorsmen to carry pepper spray with them in case of an encounter with a bear. It is also a good idea to watch out for fresh signs of bear activity. Outdoorsmen should recognize the difference between black bear and grizzly bear dung. Black bear dung is smaller and contains lots of berries and squirrel fur. Grizzly bear dung has little bells in it and smells like pepper.