Investors in AMC Entertainment (NYSE:AMC) stock received a welcome surprise from the movie theater operator after it released first-quarter earnings that impressed more than one analyst.Coupled with the revival of meme stock trading enthusiasm and AMC stock has kept a lot of the gains it has made over the past month. With the potential for a few summer blockbusters to hit the theaters in the coming weeks, there is potential for a repeat performance when AMC Entertainment releases earnings in August.Has the ...