"A copy editor can proofread a single manuscript in $45$ minutes. Over the course of a year, the copy editor proofreads all the manuscripts for $8$ research journals. Each research journal publishes $4$ issues per year and there are an average of $5$ manuscripts in each issue. If the copy editor is paid $$40$ an hour, how much is the copy editor's annual proofreading labor cost to the university?"

$"$$$2,400"$

$"$$$4,800"$

$"$$$7,200"$

$"$$$10,800"$