Answer:
2. equals the moon period of rotation.
Explanation:
Rotation and revolution are two different phenomenon, the former one involves the turning around of an object in its own axis while the latter one involves the circling of an object in its external axis.
The rate of turning around of moon in its own axis is almost equal to the rate at which it revolves around the earth in external axis. This phenomenon is called tidal locking or synchronous rotation.
The side of moon that is always towards us or earth is called lunar hemisphere, whereas the one we cannot see is called far side. Due to this synchronous rotation of moon we always see lunar hemipshere.
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