Got another problem:

The David Myer department store is open for business 10 hours per day. Last Monday, the store’s receptionist noted the number of incoming telephone enquiries about David Myer credit cards for each of the 10 hours of trading.

(a)What is the random variable of interest?

and for this one i know its the 'mean' so they couldn be mode and median am i correct ?

The receptionist reported to management that the ‘average’ number of telephone enquiries per hour for the day was 7.5.

(b) Explain whether the value 7.5 could be

(i) the mode of the day’s data.

(ii) the median of the day’s data.

(iii) the mean of the day’s data.

cheers.