What is the difference between direct democracy and representative democracy?

What is the difference between emigrate and immigrate? ?

All of the following statements about the biosphere are true except: a. light and heat from the sun do not affect the biosphere. b. the biosphere gets resources from earth's crust, hydrosphere and atmosphere. c. like "biology", the name for the biosphere comes from the greek word for life. d. the biosphere includes all living organisms on earth's surface.

If the distance between two points on the ground is 10 miles and the distance between the same two points on a map is 4 inches, what is the map scale expressed as a ratio?