The Moon revolves once on its axis each time it orbits the Earth, thus always presenting the same face to earth bound observers. However, even to the unaided eye this unchanging face shows two contrasting types of landscape dark, plain- like areas of lower relief, and brighter, decidedly more rugged regions which cover about two- thirds of the surface. Early astronomers mistakenly referred to the smooth dark areas as Maria (or sea) giving the name terrace (or land) to the bright up land regions. The terms have persisted since, even though the Moon’s surface has long been known to be completely waterless. 1. The Moon’s revolution is responsible for…………………… . A. the way it orbits the sun C. the way earth bound people can observe it B. the way its own axis is referred D. the way it is presented in history book 2. To us, the Moon’s surface……………………………. . A. never changes C. always changes B. change as we move out position D. sometimes changes 3. On the Moon, there are………………………………. . A. many kinds of landscapes C. very few contrasts B. light and dark areas D. only low plains to be observe 4. One mistake early astronomers made was…………………………… . A. to confuse the words Maria and terrace B. ignore the smooth dark area C. to consider some areas to be seas D. to think that the upland regions were bright