1. The problem statement, all variables and given/known data In Einstein's energy mass relation, the unit for the energy released is Joules, this means that the unit for the mass must be a. g b. kg c. it could be either grams or kilograms d. newtons 2. Relevant equations E = mc2 3. The attempt at a solution I believe the answer is B. because kg tend to be the standard for equations I've been working on lately. Am I correct??