Ah, OK, I see…
I don’t have that book handy right now, but often (good) sheet music gives the BPM somewhere in the top left corner of the first page, like in this example of Pat Metheny’s “Lakes”:
(Incidentally, this is a fairly fast tempo, with BPM = 180)
If that info is missing, you can play a recording of “Come as you are” and switch on the metronome (I take it it is an app on your phone, and not the old-fashioned kind!?!?) and use the “tap” function to tap along the song (the beats of the song). Then, the app will tell you how many BPMs that is, after which you go from “tap” mode to “metronome” mode, set it to that BPM and get practicing 
Or… you can “ask” the internet, which claims “Come as you are” should be played at 120 BPM.