2/4 - In music (1) the top number, or numerator, clarifies how many beats there are in one measure - in this case, there are two, (2) the bottom number, or denominator, clarifies which "type" of note receives one beat - a quarter note here.

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2/4 the top number of which means number of beats in measure
2/4 is instance of meter
2/4 the bottom # of which means type of note that gets 1 beat
2/4 clarifies number of beats in measure
2/4 clarifies type of note that gets 1 beat