The graduate students filled out the necessary applications, and submitted the required references. how is the comma used incorrectly in the sentence above? the comma attempts to separate a compound predicate. the comma attempts to set apart an essential element. the comma attempts to separate a compound subject. the comma attempts to join two independent clauses.

ANSWER: The comma attempts to separate a compound subject.

EXPLANATION: The comma is used in a sentence where a pause is necessary. In this statement, the comma is separating a compound sentence which was unnecessary. The whole sentence is joined by the word 'and' and doesn't need any other word to give a pause in the sentence.

a electronegativity decreases beacuse the size of nucleus is bigger.