Chemical weathering involves the change in the composition of rocks, often leading to a 'break down' in its form. This is done through a combination of water and various chemicals to create an acid which directly breaks down the material.
Zimbabwe is often reported to have the highest adult literacy rate on the continent. A recent news article claimed that 90% of the population is literate. The data does not back up the claims. Researched by Kate Wilkinson.
1 Japan had the highest percent of age 65 and over (23 percent) among countries with a population of at least 1 million. 2  The older population made up more than 15 percent of the population in most European countries, around 20 percent in Germany and Italy.