Hello there! I personally believe the answer will be:
the contents of a new textbook
The other ones seemed rather informal. Weekend plans with friends have no formality at all. As do the places to shop online for new shoes. The last one could be a candidate but it seems like something you would talk about with a friend or family member. Not so much your boss!
Hope this helped!
Miller used the play as a criticism of McCarthyism. The Crucible is about the witch-hunt, plus trials that took place in Salem in 1692. In this play people cared about other people's business and being accused of witchcraft was the most dangerous sin. To avoid being hanged people accused others... so yeah
