Question 4 (2 marks) XYZ wants to see if their weekly sales values have any impact on their weekly share returns (with a one-week delay). The relevant values over 8 weeks are shown below. Week Sales revenue in week ($millions) Share return for (week + 1) 1 22 -5.16% IN 14 -2.34% 3 18 2.67% 4 25 7.50% 5 30 -4.40% 6 9 4.55% V 15 -3.26% 8 21 -2.72% a) (C) Calculate Spearman's rho for this data. Show full working. [1 mark] b) (C) Calculate Kendall's tau for this data. Show full working. [1 mark]