When wildlife biologists study small animals, the animals are trapped and then anesthetized to prevent discomfort to the animal. A study of the effect of the anesthetic, Isoflurane, on eastern gray squirrels (Sciurus carolinensis) resulted in the heartbeat data presented below. The biologists were interested in comparing the effects of Isoflurane in two different seasons, winter and summer. Group Sample size Mean Standard deviationSummer 43 324.6 128.17Winter 48 373.2 50.49An initial analysis of the data revealed that it was reasonable to assume the distribution of pulses for each season is approximately normal. It was also judged to be reasonable to regard these samples as representative of the eastern gray squirrel population. If the t critical value for a 90% C. I. for is 1.6738, where represents the population mean summer eastern gray squirrel pulse and represents the population mean winter eastern gray squirrel pulse, a C. I. for the population characteristic of interest is