1 Never use a microwave or conventional oven to pre-heat your flask. 2  If your flask has not been used for some time, rinse with warm water to remove any residual odours.  DO NOT overfill your flask. Leave sufficient space in the neck to fit the stopper.
Prevalence is a measure of disease that allows us to determine a person's likelihood of having a disease. Therefore, the number of prevalent cases is the total number of cases of disease existing in a population.
Prevalence means there is a lot of something. If you get a bad grade on a paper for having a prevalence of typos, you need to proofread your work more carefully. The word is often used to describe a phenomenon that is widespread in a community, like the prevalence of a disease across a country.