The variation of maximum heart rate with age is studied in 43 sedentary male subjects. ? ? = ? ?? = 1940 ? ? = ? ?? = 7764 ? ? = ? ???? = 350,000 ? ? = ? ?? ? = 92,000 ? ? = ? ?? ? = 1,500,000 Estimate the average heart rate and its 95% intervals for a subject with age of 55? Estimate the heart rate and its 95% intervals for a subject with age of 55