The age x and resting heart rate y were measured for ten men, with the results shown in the table. x $20233037354551556063$ y $72717374747372797577$ a$)$ Estimate the average resting heart rate of all newborn baby boys. Comment on the validity of the estimate. b$)$ Compute the coefficient of determination and interpret its value in the context of age and resting heart rate. In the age range of the data, does age seem to be a very important factor with regard to heart rate?