[5 marks] Consider 4 groups (A, B, C and D) of diabetic patients who were treated by four different drugs. Their fasting HbA1c mmol/L levels were as follows. Group A Group B Group C Group D 5.6 4.3 4.8 6.1 7.2 4.9 4.4 7.2 10.3 6.9 6.8 5.1 8.4 7.8 5.8 6.1 6.3 8.8 5.3 9.1 5.4 5.6 7.5 8.1 6.6 6.2 5.7 8.1 6.3 7.2 5.3 5.2 If the data in groups A and C are non-normal but normal in groups B and D, what are the statistical methods that could have been used to analyse the difference between these four treatment groups? Justify your