25. Radon-222 has a half-life of 3.82 days. After 6.73 days, 132 mg remain from the original sample. (a) (2 points) What was the initial mass of the Radon-222 sample? (b) (2 points) Using the initial mass from part a), how long before the sample decays to a mass of 5.00 mg? (c) (2 points) The figure below shows Radon (Rn) and some of its neighbouring clements. Use the figure to write a balanced reaction cquation for the alpha decay of Radon-222. 82 83 84 85 86 Pb Bi Po At Rn Lead Bismuth Polonium Astatine Radon