ATOMS, ISOTOPES AND RADIOISOTOPES: Atoms, Isotopes, Radioisotopes, Artificial Transmutation: How radioisotopes are manufactured Radioactivity and how it is detected: Alpha decay, Beta Decay, Gamma decay, How radiation is detected Properties of alpha, beta and gamma radiation: Alpha particles, Beta particles, Gamma rays, The ionising abilities of alpha, beta and gamma radiation, The energy of Alpha-Beta-Gamma radiation Half Life and activity of radioisotopes: Decay Series Radiation dose and its effect on humans: Measuring radiation exposure, The effects of radiation I've got a test coming up and it's my fault for not listening and paying attention in class as I thought it will be easy but it ain't. I need a way to learn all this to answer from simply questions like how many protons,neutrons and nucleons are in the following nuclides to a radioactive isotope has a life of 1 hour, if a sample initially contains 100 mg of this isotope, which one of the following correctly gives the amount of the radioisotope remaining after 2 hours have elapsed: none,50mg,25mg,100mg... Etc. Questions like these and harder will be on the test like drawing graphs etc. Thank you.