Which sentence below shows correct use of em dashes?

by the end-of-the-story, no one could believe it the main-character, was dead.
by – the end of the story no one could believe it, the main – character was dead.
by the end of the story, no-one could believe it the main, character – was dead.
by the end of the story – no one could believe it – the main character was dead.

Ineed advice. i have a lot of friends at school but recently my best friend for some reason didn’t like our friend group. she wanted to switch to a new table during lunch. she said she found a new table where we would be welcomed if i wanted to come. i agreed because i knew i would continue to talk to them outside of lunch. after a month or two, my best friend got mad at our new lunch table group. so she left for a day or two, but i stayed because i actually kinda liked it there, even if it was kinda crazy. then she came back to the table. eventually i started to miss my old friends at my old lunch table. so i went over there for one lunch. then after lunch i sat at my new lunch spot before the bell rang. they all called me a traitor. so now i sit with my old lunch group, which is fine because i missed them, but i also miss my new, now old, lunch table. what should i do? p.s. sorry if you loose your last brain cells trying to understand this.

The author most likely uses the word monstrous rather than the word “unpleasant” because it has a more positive connotation than the word “unpleasant.” a more negative connotation than the word “unpleasant.” a more neutral connotation than the word “unpleasant.” almost the same connotation as the word “unpleasant.”

Underline the ic or ic's and place the proper punctuation if needed. the board of trustees admits that it made a mistake because the employees were toolazy nothing happen to the board