0/1 Points] DETAILS PREVIOUS ANSWERS TANAPMATH7 3.3.008. MY NOTES ASK YOUR TEACHER Radioactive Decay The radioactive element polonium decays according to the law given below where Q, is the initial amount and the time t is measured in days. Q(t) = Q . 2-(t/140) If the amount of polonium left after 700 days is 90 mg, what was the initial amount present? 92.8125 x mg 0/1 Points] DETAILS PREVIOUS ANSWERS TANAPMATH7 3.3.020. MY NOTES ASK YOUR TEACHER Reliability of Computer Chips The percentage of a certain brand of computer chips that will fail after t years of use is estimated to be P(t) = 100(1 - e-0.1t ). What percentage of this brand of computer chips are expected to be usable after 7 years? (Round your answer to one decimal place.) 50.3 X %