(Lab 11: 1- & 2-Sample T-Tests and T-Intervals) Because cardiac deaths appear to increase after heavy snowfalls, an experiment was designed to compare cardiac demands of snow shoveling to those using an electric snow thrower. Ten subjects cleared tracts of snow using both methods, and their maximum heart rates (beats per minute) were recorded during both observed activities. The following results were obtained:

Method Used	Mean Heart Rate (BPM)	SD Heart Rate
Manual	175	15
Electric	124	18

Building a 95% confidence interval for each methodology, discuss which methodology increases the risk for cardiac death. Is this difference enough to make a valid claim? Why? Make sure to illustrate each confidence interval and interpret them to argue your reasoning.

(Based on data from "Cardiac Demands of Heavy Snow Shoveling," by Franklin et. al., Journal of the American Medical Association, Vol. 273, No. 11)

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