In Situation M, how many runners will score if B5 passes R2 at first?

When B5 passes R2 at first base, it creates a specific situation based on the rules governing base running and scoring. In this scenario, R2 is out for passing a preceding runner (R1), since a runner cannot pass another runner successfully on the same base path. However, the key detail is that R1 was already on base at the time of the event and advances to home plate as a result of B5’s hit, which is considered a home run.

Under the rules of baseball, when a home run is hit, all runners on base at the time of the hit are allowed to score, regardless of what happens with later runners who may not adhere to proper baserunning rules. In this situation, R1, having already touched home plate, is allowed to score despite R2 being declared out for passing.

Additionally, since R2 is out and cannot score, that does not affect R1’s ability to touch home plate. Therefore, while R2 is out, R1 successfully scores, leading to the conclusion that both runners, R1 and B5 (who will also score on the home run), contribute to the scoring.

It's important to recognize that the out of R2 does not negate the scoring of