Libby is drawing. She places her red pencil behind her ear to use another colored pencil. After a minute Libby doesn’t feel the pencil behind her ear anymore and she forgets it is there. Libby is most likely experiencing

Habituation.

Explanation:

Habituation refers to the psychological learning mechanism where the reaction to a stimulus is reduced after repeated exposure to it. This definition suggests that because of repeated exposure to it, an organism can tend to ignore a stimulus. It happens in everyday life but we still do not realize it to a large extent. As per the question,  Libby doesn’t feel the pencil behind her ear as she left it there and forgot about it is an example of habituation.

buildings

explanation:

giant impact theory - the moon was formed from the collision between earth and another mars-sized body.

colliding planetesimals hypothesis - the moon was formed from the same cloud of material as earth.

capture hypothesis - the moon was locked into orbit by earths gravity as it was passing by it.

accretion hypothesis - the moon was formed from collisions and combining of planetesimals.

i think this is right, if not and you know better let me know.