The large data set contains data on cars from 2002 and 2016. A selection of data relating to the engine size and CO2 emissions often BMW cars from 2016 is given above.

(i) Using your knowledge of the large data set, give two possible reasons for the CO2 emissions value of 0 g/km. Given that the corresponding engine size is also recorded as 0 cm³, state which of your reasons you think is most likely.

(ii) Considering your answer from part (i), use the rest of the values to find the mean and standard deviation of the CO2 emissions of the BMW cars from 2016.

1.2. Given that in 2002 the mean CO2 emissions of BMW cars was 215.5 g/km, use your knowledge of the large data set to give a possible reason for the change in the mean CO2 emissions from 2002 to 2016.