Answer: £20 doubling at the end of each year for 5 years
From the question, Stephen would want to select one option which gives the highest amount of profit. I mean, even if you were to select one, you would obviously try calculating all the 4 choices to see which one makes you earn the most money. Now let's conduct the workout and see which one will earn us the most £ in 5 years:
<u>Option 1:</u>
ans: £ 638.142
<u>Option 2:</u>

ans: £ 600
<u>Option 3:</u>

ans: £ 637.601
<u>Option 4:</u>

ans: £ 640
Out of all the calculated answers, you can see that option 4 has the highest amount. So that's it. By the way, I might do some incorrections in some calculations because I am not good at long maths, but yes i hope I did it all right!
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hope it helped
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