Here is the item:
Class with Professor Rogers was a nightmare: the clock
seemed stuck in place, the air conditioner blew
inadequate cool, and a fluorescent bulb buzzed
overhead.
Super choice! When you list grammatical items, you must use parallel structure. In this item, you have three short main clauses: the clock seemed stuck in place, the air conditioner blew inadequate cool, and a fluorescent bulb buzzed overhead. The list is thus parallel.