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**Hapa** The half life of plutonium-239 is 24,360 years. The maximum amount an adult human can handle without injury is .13 micrograms (.000000013 grams). suppose a researcher possesses a 1-gram sample of plutonium - 239. the amount "A" (in grams) after "t" years is A(t) = 1 x (1/2)^ t/360

a) How much of 1-gram sample will remain after 10,000 years?

b) How long will it take before there is .000000013 grams left?

My issue is this: For part "A", how do I input 1/2 to the 10000/36th power on my calculator. I Have a TI-30Xa, yet I have been unable to figure out how to enter this formula.

For part B, is it as simple as counting the number of half lives that pass until I get an amount less than .13 micrograms?

Thanks in advance for your help!