How much money will there be in an account at the end of 8 years if $9000 is deposited at 4% interest compounded semi-annually? (Assume no withdrawals are made.) The amount after 8 years will be $ (Round to the nearest cent as needed.) loga 2 0.301 and loga5 0.699. Use one or both of these values to evaluate loga8. The decay rate of a certain chemical is 9.7% per year. What is its half-life? Use the exponential decay model P(t) = P0e-kt where k is the decay rate, and P0 is the original amount of chemical. The half-life of the chemical is years.