I wanted to make bread this weekend, but didn't because I suspect my yeast are dead. I am using the regular dried yeast, which isn't due to expire until March 2003. I was following my ususal step of proofing the yeast. But after 15 minutes I don't see any foam, no bubbles, nothing! I thought maybe I might have killed the yeast with too hot water, so I tried again with a second batch, with just tepid water, still nothing. What's going on? Are my yeast dead? How can I check? Is there another way besides proofing?