I dont undertand how the instructor claculates to get to the final answer. i also dont know when i should be using APPS vs. hand solution...or can these word problems always be solved by APPS in thr TI-84? I really just need a step by step explanation. This is the begining of the class and really need to master thr basics.

You can invest in an account that pays simple interest or an account that pays compound interest. In either case, you plan to invest $2,100 today and both accounts have an annual interest rate of 5 percent. How much more interest will you receive in the 10th year in the account that pays compound interest? Multiple Choice O $75.05 O $7074 O $5789 $7156 $105.00 You have just leased a car that has monthly payments of $365 for the next 4 years with the first payment due today. If the APR is 6.84 percent compounded monthly, what is the value of the payments today? Multiple Choice $13.979.07 $15,908.19 $14,88973 $15,376,98 $15.289.83 You have researched your dream around-the-world vacation and determined that the total cost of the vacation will be $36,000. You feel you can earn an APR of 10.8 percent compounded monthly and plan to save $440 per month until you reach your goal. How many years will it be until you reach your goal and enjoy your well-deserved vacation? Multiple Choice 5.13 years 6.82 years 538 years 4 74 years 5.87 years If you earn an annual interest rate of 9.5 percent, how many years will it take to quadruple your money? Multiple Choice 13.89 years 12.22 years o 13,37 years O 15.28 years 14.10 years