In an epidemiological study of asbestosis (a chronic lung disease that severely impairs gas exchange by causing progressive scarring of the alveoli), the following statistics were reported for a specific industrial region:
Calculate the total number of people in this region who are estimated to have asbestosis (both diagnosed and undiagnosed) and were employed in the shipbuilding or construction industries before 1980. Show your working.
16 exam-style questions on Edexcel IGCSE Biology Gas exchange. Each one has a worked solution and a mark scheme showing where the marks go.