How do hip bones of a snake provide evidence for the evolution of snakes?

How does the release of trapped gases in magma cause a volcano to erupt? a. they push the magma up the pipe and then are reabsorbed into the magma chamber. b. they cause the magma to change chemically into lava. c. the gases form vents that allow the magma to flow out. d. the gases rush out and carry the magma with them.

What did hunter gathers do to alter the environment?

During convection, less dense fluid rises and denser fluid sinks.