1. [0/1 Points] DETAILS PREVIOUS ANSWERS Simplify 6109 6(36). 168 X Need Help? Read It 2. [-/1 Points] DETAILS Find the associated exponential decay or growth model. (Round all coefficients to three significant digits.) Q = 1,600 when t = 0; half-life = 1 Q = Need Help? Read It Watch It 3. [-/1 Points] DETAILS Find the associated exponential decay or growth model. (Round all coefficients to three significant digits.) Q = 2,000 when t = 0; doubling time = 4 Q = Need Help? Read It Watch It4. [-/1 Points] DETAILS Find the associated half-life time or doubling time. (Round your answer to three significant digits.) Q =Qe-6t Need Help? Read It Watch It 5. [-/1 Points] DETAILS Convert the given exponential function to the form indicated. Round all coefficients to four significant digits. f(x) = 32 ; f(x) = Ab* F(x) = Need Help? Read It 6. [-/1 Points] DETAILS Convert the given exponential function to the form indicated. Round all coefficients to four significant digits. At) = 2.1(1.008)"; At) = Qek F(t) = Need Help? Read It7. [-/1 Points] DETAILS MY NOTES How long (in years) will it take a $300 investment to be worth $800 if it is continuously compounded at 9% per year? (Give the answer to two decimal places.) yr Need Help? Read It Watch It 8. [-/1 Points] DETAILS MY NOTES How long, to the nearest year, will it take an investment to double if it is continuously compounded at 9% per year? yr Need Help? Read It Watch It 9. [-/1 Points] DETAILS MY NOTES Long-Term Investments This exercise is based on the following table, which lists interest rates on long-term investments (based on 10-year government bonds) in several countries in 2014.t Country U.S. Japan Germany Australia Brazil Yield 2.5% 0.5% 1.0% 3.5% 4.2% If you invest $10,200 in the United States, and the interest is compounded monthly, when, to the nearest month, will your investment be worth $30,000? months Need Help? Read It10. [-/1 Points] DETAILS This exercise is based on the following table, which lists interest rates on long-term investments (based on 10-year government bonds) in several countries in 2014. + Country U.S. Japan Germany Australia Brazil Yield 2.5% 0.5% 1.0% 3.5% 4.2% How long, to the nearest year, will it take an investment in Brazil to double its value if the interest is compounded every 3 months? yr Need Help? Read It Watch It 11. [-/2 Points] DETAILS The rate of auto thefts doubles every 8 months. (a) Determine, to two decimal places, the base b for an exponential model y = Ab of the rate of auto thefts as a function of time in months. b = (b) Find the tripling time to the nearest tenth of a month. months Need Help? Read It12. [-/2 Points] DETAILS MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER The half-life of cobalt 60 is 5 years. (a) Obtain an exponential decay model for cobalt 60 in the form Q = Qreck. (Round the decay constant to three significant digits.) Q (t) = (b) Use your model to predict, to the nearest year, the time it takes one third of a sample of cobalt 60 to decay. yr Need Help? Read It Watch It 13. [-/1 Points] DETAILS MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Soon after taking an aspirin, a patient has absorbed 300 milligrams of the drug. If the amount of aspirin in the bloodstream decays exponentially, with half being removed every 2 hours, find, to the nearest 0.1 hour, the time it will take for the amount of aspirin in the bloodstream to decrease to 200 milligrams. hr Need Help? Read It 14. [-/1 Points] DETAILS MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER After a large number of drinks, a person has a blood alcohol level of 120 mg/dL (milligrams per deciliter). If the amount of alcohol in the blood decays exponentially, with one fourth being removed every hour, find the time it will take for the person's blood alcohol level to decrease to 60 mg/dL. (Round your answer to one decimal place.) hours Need Help? Read It Master It
