Sammie and joel invest their money with the grabitall bank. sammie invests £320 in an account that pays 4% simple interest each year. joel invests £420 in an account that pays 3% simple interest each year. a) who earns the most interest each year? show your working? b) how much money will joel have after 5 years? make sure you give the total and not just the interest. include workings out.