Ow many valence electrons do atoms in group 1, group 2, group 15, group 16, group 17 have?

When a septic tank backs up a goes in to clean it out

Describe what happens to the molecules as water goes from ice to liquid to vapor. be sure to explain what happens to the temperature during the phase changes.

The gulf stream is a warm water current that flows away from the equator to northern europe. witch of these does it cause. a. crashes of warm and cool water in the ocean b. colder climates near the equator c. large waves on the cost of europe d. warm climates in northern europe