4. The petrol stations A - J, which are situated in areas of similar traffic density, are ranked according to their service quality, forecourt size, and petrol price. Rank 1 indicates the best service, largest forecourt, and lowest price. The results including the average weekly petrol sales (in '000 gallons) are given below: Station Service Forecourt Petrol Sales Quality Size Price ('000 of gallons) A 3 8 2 47 B 4.5 CO 20 4 10 8 23 8 2 36 A 36 31 10 CO 33 H 9 6 10 28 - 4.5 42 6 7 6 24 (a) Carry out calculations to decide whether (i) price of petrol, or (ii) service quality, is likely to be more important factor in determining petrol sales, or whether neither appears to be important. (b) Is there any evidence to suggest that the stations with larger forecourts give better service quality