Radioactive Decay: Polonium-215, 
Po, undergoes alpha decay with a half-life of 1.8 ms.(a) What percent of the original polonium-215 is left after 0.010 s?(b) How many protons and neutrons does the daughter nucleus contain?
What will be an ideal response?
(a) 2.1% (b) 82 protons, 129 neutrons
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