Which of the following best applies to the distinction between the "long run" and the "short run"?

The short run is a period of approximately 1-6 months while the long run is any time frame which is longer.

In the short run, only new firms may enter, while in the long-run, firms may either enter or exit the market.

The rationing function of price is a short-run phenomenon whereas the guiding function is a long-run phenomenon.

All of the above