Which of these is the largest unit of linear distance?
a. au
b. parsec
c. light-year
d. arcsecond

What is the correct order of events in the water cycle?

Air masses are characterized by various properties including temperature humidity air temperature pressure and wind speed . which of the following air masses is associated with low relative humidity and high temperature

What evidence does the writer give to support his argument about coral reefs? a) he speaks of the activities of coral polyps. b) he describes the composition of the great barrier reef. c) he emphasizes the ways in which coral reefs are fragile. d) he points out the ways that scientists do research on the reefs.