I will check with Thor and Calypso I might just use something I already know the weight of and compare it to their weight or use a scale. I could convert it on my cell phone. My phone can convert lbs. into grams and kg.
I would hope that you could do that without a cell phone or calculator, lol. Too funny, roommate and I were talking about this earlier... What math does one have to know to graduate from high school these days?
-Kathy