Scientists at the hopkins memorial forest in western massachusetts have been collecting meteorological and environmental data in the forest data for more than 100 years. in the past few years, sulfate content in water samples from birch brook has averaged 7.48 mg/l with a standard deviation of 1.60 mg/l.

Edward tolman explained the results of his study by theorizing that the rats were learning about the maze during every trial but they a. were agitated because other groups were getting reinforcement b. could not remember how to demonstrate it without reinforcement c. were not motivated to demonstrate it without reinforcement d. seemed to be too lazy to actually work without reinforcement