Q9,11&Q13 needed to be solved correctly in 1 hour and get the thumbs up please show me neat and clean work for it By hand solution neededYou have to do both questions please Check Your Understanding 5.21. One thousand dollars is to be invested in a bank for 4 years.Would 8% interest compounded semiannually be better than73% interest compounded continuously?EXERCISES 5.21. Savings Account Let A(1) = 5000e0.04 be the balance in a sav-ings account after / years.(a) How much money was originally deposited?(b) What is the interest rate?(c) How much money will be in the account after 10 years?(d) What differential equation is satisfied by y = 4(1)?(e) Use the results of parts (c) and (d) to determine how fastthe balance is growing after 10 years.(f) How large will the balance be when it is growing at therate of $280 per year?2. Savings Account Let A(1) be the balance in a savings accountafter years, and suppose that A(1) satisfies the differentialequationA'(t) = .045A(1), A(0) = 3000.(a) How much money was originally deposited in the account?(b) What interest rate is being earned?(c) Find the formula for A(1).(d) What is the balance after 5 years?(e) Use part (d) and the differential equation to determinehow fast the balance is growing after 5 years.(f) How large will the balance be when it is growing at therate of $270 per year?3. Savings Account Four thousand dollars is deposited in a savingsaccount at 3.5% yearly interest compounded continuously.(a) What is the formula for A(1), the balance after years?(b) What differential equation is satisfied by A(1), the balanceafter years?(c) How much money will be in the account after 2 years?(d) When will the balance reach $5000?(e) How fast is the balance growing when it reaches $5000?4. Savings Account Ten thousand dollars is deposited in a savingsaccount at 4.6% yearly interest compounded continuously.(a) What differential equation is satisfied by A(7), the balanceafter years?(b) What is the formula for A(1)?(c) How much money will be in the account after 3 years?(d) When will the balance triple?(e) How fast is the balance growing when it triples?5. Investment Analysis An investment earns 4.2% yearly interestcompounded continuously. How fast is the investment grow-ing when its value is $9000?6. Investment Analysis An investment earns 5.1% yearly inter-est compounded continuously and is currently growing atthe rate of $765 per year. What is the current value of theinvestment?7. Continuous Compound One thousand dollars is deposited ina savings account at 6% yearly interest compounded continu-ously. How many years are required for the balance in the ac-count to reach $2500?5.2 Compound Interest 269Solutions can be found following the section exercises.2. A building was bought for $150,000 and sold 10 years laterfor $400,000. What interest rate (compounded continuously)was earned on the investment?8. Continuous Compound Ten thousand dollars is invested at6.5% interest compounded continuously. When will the invest-ment be worth $41,787?9. Technology Stock One hundred shares of a technology stockwere purchased on January 2, 1990, for $1200 and sold onJanuary 2, 1998, for $12,500. What rate of interest compound-ed continuously did this investment earn?10. Appreciation of Art Work Pablo Picasso's Angel Fernandez deSoto was acquired in 1946 for a postwar splurge of $22,220. Thepainting was sold in 1995 for $29.1 million. What yearly rate ofinterest compounded continuously did this investment earn?11. Investment Analysis How many years are required for an in-vestment to double in value if it is appreciating at the yearlyrate of 4% compounded continuously?12. Doubling an Investment What yearly interest rate (compoundedcontinuously) is earned by an investment that doubles in 10 years?13. Tripling an Investment If an investment triples in 15 years,what yearly interest rate (compounded continuously) does theinvestment earn?14. Real Estate Investment If real estate in a certain city appre-ciates at the yearly rate of 15% compounded continuously,when will a building purchased in 2010 triple in value?15. Negative Interest Rates Suppose that the bank in Example 3increased its fees by charging a negative annual interest rate of-.9%. Find the balance after two years in a savings account ifPo 10, 000 SFr.16. Negative Interest Rates How is the account in Exercise 15changing when the balance is 9,500 SFr?17. Real Estate Investment A farm purchased in 2000 for $1 mil-lion was valued at $3 million in 2010. If the farm continues toappreciate at the same rate (with continuous compounding),when will it be worth $10 million?18. Real Estate Investment A parcel of land bought in 1990 for$10,000 was worth $16,000 in 1995. If the land continues toappreciate at this rate, in what year will it be worth $45,000?19. Present Value Find the present value of $1000 payable at theend of 3 years, if money may be invested at 8% with interestcompounded continuously.20. Present Value Find the present value of $2000 to be receivedin 10 years, if money may be invested at 8% with interest com-pounded continuously.21. Present Value How much money must you invest now at 4.5%interest compounded continuously to have $10,000 at the endof 5 years?22. Present Value If the present value of $1000 to be received in5 years is $559.90, what rate of interest, compounded continu-ously, was used to compute this present value?

8. Continuous Compound Ten thousand dollars is invested at 6.5% interest compounded continuously. When will the invest- ment be worth $41,787? 9. Technology Stock One hundred shares of a technology stock were purchased on January 2, 1990, for $1200 and sold on January 2, 1998, for $12,500. What rate of interest compound- ed continuously did this investment earn? 10. Appreciation of Art Work Pablo Picasso's Angel Fernandez de Soto was acquired in 1946 for a postwar splurge of $22,220. The painting was sold in 1995 for $29.1 million. What yearly rate of interest compounded continuously did this investment earn? 11. Investment Analysis How many years are required for an in- vestment to double in value if it is appreciating at the yearly rate of 4% compounded continuously? 12. Doubling an Investment What yearly interest rate (compounded continuously) is earned by an investment that doubles in 10 years? 13. Tripling an Investment If an investment triples in 15 years, what yearly interest rate (compounded continuously) does the investment earn?