Car parking spaces in a city centre are at a premium. The costs of parking a car for a whole day in ten public car parks within the city, and the distances between those car parks and the city centre are:
(a) Assuming that the cost of parking is dependent on the distance the car park is from the city centre, plot the data on a scatter diagram.
(b) Find the value of the Pearson correlation coefficient and indicate what conclusions should be drawn from it.