How do we pronounce the "s"in verbs like "tries/flies"? Is it /z/ like in "plays"or "says"?Thanks.

Question

Answer

yes, it is the same, because the previous sound to the "S" is a voiced sound, so the plural is voiced too ( /z/)

Answer

Yes.
For the verbs that end in /p/, /t/ ,/k/,/f/,we pronounce final "s":/s/.
 end in /s/,/z/,/ʃ/,/tʃ/,/dʒ/,we pronounce final "s":/iz/.
others,we pronounce final "s":/z/.

Answer

The (S) in question I would say is pronounced like the s in plays, yes that is correct
also like the s in sound.

I hope this was of help to you.