Explain one reason why Tharun may earn more than a cleaner.

Wage differentials between occupations can be explained by the theory of supply and demand in the labour market. A veterinary surgeon's job requires years of university education and specialised training. This creates a high barrier to entry, limiting the supply of people who can do the job. In contrast, cleaning is a low-skilled job with minimal training requirements, meaning there is a very large supply of potential workers. Given that there is demand for both services, the relative scarcity of veterinary surgeons compared to the abundance of cleaners leads to a much higher equilibrium wage for vets.