A person x inches tall has a pulse rate of y beats per minute, as given approximately by yequals600 x Superscript negative 1 di
vided by 3 for 30 less than or equals x less than or equals 75. What is the instantaneous rate of change of pulse rate for the following heights? (A) 39-inches (B) 71-inches What is the instantaneous rate of change of pulse rate for a 39 inch tall person?