for madamprofessor only

1. Many people confuse the large void in the ozone layer with global warming. Can you distinguish between the two phenomena? Explain how each process may harm living things.

2.

On a given day in the winter in St. Louis, Missouri it began snowing in the morning. The snow changed to rain by noon, later in the afternoon sleet was falling which turned to snow, and by evening rain was freezing on bridges and roadways. Explain how such a sequence of precipitation might occur.