How do we determine the values of any given fission reaction? How do we answer questions like: A decrease in mass of 3.48x10(to the power of -28) kg occurs. Express the energy equivalent of this in terms of joules and MeV. I keep reading and reading but can't understand. I search online but still can't get the general and advanced concepts of Physics. It asks all these worded questions which I don't get, is there a easier/better way to practice Energy from The Nucleus?? Thank you.