Final answer:
The dash in the sentence is used to set off further detail or explanation.
Step-by-step explanation:
The dash in the sentence is used to set off further detail or explanation. In the given sentence, the dash is used to provide additional information about what the homework was about. It helps to clarify and expand on the idea of finishing the homework by indicating the topic. The dash separates the main clause from the detail, giving it emphasis and making it stand out.
Learn more about The use of dashes in sentences