[填空题]
The half-life, T, in yearsc +z8x:i /bhg,q 1lgyq, of a radioactive isotope c+m;70ddjh twm5 lh7:x itiu(czm+ / nnan be modelled by the functn+itmndt7u:(/7mjh+c zi x hmwl0;5d ion
T(k)=$\frac{ln0.5}{ln(1-\frac{k}{100})}$,0where k is the decay rate, in percent, per year of the isotope.
1.The decay rate of Hydrogen-33 is 5.5 % per year. Find its half-life.
The half-life of Uranium-232 (U-232) is 68.9 years. A sample containing 250 grams of U-232232 is obtained and stored as a side product of a nuclear fuel cycle. ≈
2Find the decay rate per year of U-232. k = %
3.Find the amount of U-232 left in the sample after:
(1)68.9 years; grams
(2)100 years. ≈ grams