Three members of a family were all born on 4 July 1950. Archie is a teacher and earns 40,000 pounds per year. his cousin bob works part time in a supermarket and earned 20,000 pounds in 2023-24. bob also received 20,000 pounds in dividends on his share portfolio. the third cousin Colin is retired with annual pension of 10,000 pounds and received 30,000 pounds of dividends on his large portfolio of shares. calculate the income tax liability in 2023-24 for Archie, bob and Colin.