How do electric and magnetic forces act on different objects

What does si stand for, when referring to a system of measurement

Atemperature inversion can cause a warm air mass to move over a colder air mass. this traps the colder air mass and prevents surface air from rising. this may result in which of these? a) smog b) acid rain c) freezing rain d) a thunderstorm

You can melt ice by applying pressure because the solid/liquid line has a slope.