In a study of 103 randomly selected male smokers, the average heart rate was found to be 115 beats per minute. The margin of error in the survey was found to be plus or minus 7.85 beats per minute. 

a. Compute the sample statistic from this study. Use appropriate notation to label the statistic. 

b. Construct a 95% interval estimate using this information. 

c. What quantity is the interval estimate trying to capture? Use the appropriate notation and words. 

d. Interpret the confidence interval.