The mean heart rate among adults using wearable devices is 64.5 beats per minute, and the mean heart rate 71.8 beats per minute in adults not using wearable devices. Suppose the pooled standard deviation is given, 16.8 beats per minute. In our sample, we have 75 adults who use wearable devices and 75 adults who do not use wearable devices. Please answer the following questions. (10%)

1. Please specify your null hypothesis, research hypothesis, and significance level.
2. Compute the t statistic for the two independent samples test for means. What is the degrees of freedom for the t statistic?
3. Compute the p-value associated with your t statistic. (hint: use t.dist.2t function in EXCEL for two sided p-value)
4. Compare your p-value and the pre-determined significance level, which is larger, which is smaller? What would you conclude the results for your hypothesis?