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The answer is c hope this

Gamma rays  and beta particles are all  used  to treat internal organs. x-rays  are produced by firing electrons at a metal target and  gamma rays  are emitted by the nucleus of radioactive atoms.  gamma rays  are  used  to kill cancer cells, and to  medical  equipment and in radioactive tracers.

Part (a) is relatively straight forward.there are 4 aces in a standard 52-card deck. so the probability that an ace is picked is just 4/52.part (b): note that there are 4 suits in a standard 52-card deck. so picking hearts will be 13/52 or 1/4.part (c): the probability condition or means we need to add the two probabilities because we do not want them simultaneously. so, we end up getting pr(ace) + pr(heart).from part (a), we found that picking an ace had a probability of 4/52, which is reduced down to 1/13.from part (b), we found that picking a heart had a probability of 1/4.so, the probability of an ace or a heart is 1/13 + 1/4 = 4/52 + 13/52 = 17/52.