Soon Monday I started some Wyeast American Ale II. It was an older package, and the Mr. Malty calculator said it had 3% viability.I had just been agitating it by hand, and took it into the bedroom with me on Monday night. That night the fire went out, and the room got pretty cold. Maybe 50°. I slowly warmed it back up into the mid 60s and agitated it throughout the day yesterday, but there were no obvious signs of life. I figured that either because of the age or the drop in the temperature the yeast wasn't viable at all, and I needed to get a new pack. This morning as soon as I touched it it sprang to life, and produce a nice rich foam as soon as I agitated it. Is it okay to brew with?