17 Lower limit of range H= (220 - a) 10 4 Upper limit of range H = -(220 - a) 5 .. . a. What is the lower limit of the heart range, in beats per minute, for a 28-year-old with this exercise goal? The lower limit of the heart range is 134 beats per minute. (Round to the nearest integer as needed.) b. What is the upper limit of the heart range, in beats per minute, for a 28-year-old with this exercise goal? Thus, the upper limit of the heart range is beats per minute. (Round to the nearest integer as needed.)