4 In 2021, there were extensions and contractions in demand for a number of South African products.
In that year, a South African court stopped a multinational company (MNC) exploring for oil along
South Africa’s coastline. South Africa experienced an increase in output, driven largely by the growth
in its tertiary sector. However, its unemployment rate was 35%, a long way from full employment.

(a) Define an extension in demand. [2]

(b) Explain two external costs that may be caused by exploring for oil. [4]

(c) Analyse how growth in a country’s tertiary sector can increase its living standards. [6]

(d) Discuss whether or not workers who lose their jobs are likely to stay unemployed for a long
time. [8]