Aproduct that is popluar for a short period of time

When water freezes, it . contracts expands

In the diagram below, the northern hemisphere would be in what season at position a a.fall b. winter c.summer d.spring

Which of the following types of pollution is most responsible for large numbers of deaths worldwide because of unsafe drinking water? (a) nutrient pollution (b) thermal pollution (c) pathogen pollution (d) sediment pollution