Final answer:
The question seems to be related to a specific event in a work of fiction, and without the relevant context from the text, an accurate answer cannot be provided.
Step-by-step explanation:
The question about when the mystery of the stolen broach was solved so that Anne could still go to the picnic is likely pertaining to a narrative or a story from a work of fiction in an English class, considering the context provided. Without specific information about the time the mystery was solved, it's not possible to give an exact answer, as the passages provided do not contain direct details about the broach mystery being solved. These details would likely be found within the specific text being studied, which would provide the necessary context to answer the question. It's important in these types of questions to refer back to the text in question for details about events and timings.