An employee wants to invest $60,000 in a pension plan. One investment offers 5% compounded semiannually. Another offers 4.25% compounded continuously. (a) Which investment will earn more interest in 5 yr? (b) How much more will the better plan earn? (a) After 5 years, will earn more interest. (b) The better plan will earn $ more. (Round to the nearest cent as needed.) If 10g of a radioactive substance are present initially and 2 yr later only 5.0g remain, how much of the substance, to the nearest tenth of a gram, will be present after 3yr ? After 3yr, there will be g of the radioactive substance. (Do not round until the final answer. Then round to the nearest tenth as needed.) The values of y,y0, and t are given. For an equation of the form y=y0ekt, give the exact value of k in terms of natural logarithms. y0=120,t=3,y=40 k= (Use integers or fractions for any numbers in the expression.)