Heidi waited for somebody, anybody to answer. She knew the answer of course, but she always liked to make sure nobody else also knew the answer before she answered. Seeing that nobody was answering, she could feel a few people glance at her expectantly. Just a few more nanoseconds she waited, for the exact time when her answering went from a know-it-all speaking over everyone, to the saviour answering the question before the teacher answered their own question and the whole class loses. 

She raised her hand, and when Dr. McCoy motioned for her to continue, she started speaking, clearly yet still quietly, almost to herself; "Determinism is the belief that everything that happens is predetermined, and there is only one way anything in the future will actually happen. This would basically mean that we would have no free will and our choices wouldn't matter, as in a sense, they were already made for us."