Final answer:
The part of the sentence that functions as an adverb is 'to better augment'.
Step-by-step explanation:
The part of the sentence that functions as an adverb is 'to better augment'. Adverbs modify verbs, adjectives, or other adverbs, and in this sentence, 'to better augment' modifies the verb 'added'. It tells us how the administrator added new personnel to the existing sales force.
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