6.5 In an effort to link cold environments with hypertension in humans, a preliminary experi- ment was conducted to investigate the effect of cold on hypertension in rats. Two random samples of 6 rats each were exposed to different environments. One sample of rats was held in a normal environment at 26C. The other sample was held in a cold 5C environment. Blood pressures and heart rates were measured for rats for both groups. The blood pressures for the 12 rats are shown in the accompanying table. a. Do the data provide sufficient evidence that rats exposed to a 5C environment have a higher mean blood pressure than rats exposed to a 26C environment? Use a = .05. b. Evaluate the three conditions required for the test used in part (a). c. Provide a 95% confidence interval on the difference in the two population means. 26C 5C Rat Blood Pressure Rat Blood Pressure 12345 152 7 384 157 179 182 10 176 11 6 149 89612 369 354 375 366 423