A little bit of additional information, from Jon via Rene:
If someone thinks their mead is not at all active, they can add 1/4 tsp yeast per the instructions below. (Available by advance request at the 8/7 LBB Club meeting at EDCO or for pickup later).
Get 1/2 cup of water to 110 degrees and mix in 1 tablespoon of sugar or honey preferably. Then add 1/4 tsp of yeast. After that, let it cool down (about 20 minutes) to at least 80-85 degrees before adding to the mead. Half way through can add a tsp more honey.
Keep in mind that things like temperature, amount of sugars and yeast, etc. affect fermentation rate.