The accompanying summary quantities resulted from a study in whichwas the number of photocopy machines serviced during a routine service call andwas t

The accompanying summary quantities resulted from a study in whichwas the number of photocopy machines serviced during a routine service call andwas the total service time (min).(a) What proportion of observed variation in total service time can be explained by a linear probabilistic relationship between total service time and the number of machines serviced? (Give the answer to three decimal places.)(b) Calculate the value of the estimated standard deviation. (Give the answer to three decimal places.)=What is the number of degrees of freedom associated with this estimate?