Motorola V3c Cellular Phone

My son had the phone in his backpack and the front screen got cracked. The screen still works but you can't hear sound now. When you call him it only vibrates but no sound. Also if you go to Media Gallery and try to play songs, it shows that they are playing but you can't hear them. When you push buttons, they make a sound. Is there anything we can do to fix this. Is the speaker located under the fron screen that go cracked or what? Thanks so much