New York Times: Use apostrophes for plurals of abbreviations that have funds letters and durations: M.D.’s, C.P.A.’s. Also use apostrophes for plurals formed from one letters: He gained A’s and B’s on his report card. Thoughts your p’s and q’s. It's fascinating that guides by exactly the same publisher, but https://hyperbookmarks.com/story19966572/not-known-details-about-used-cars-uk