O H 2. a) For how long would $6000 need to be invested, at 6.4% simple interest, to earn $1200 in interest? b) How long would it take if the interest for part a) was paid yearly? c) How long would it take if the interest was paid quarterly? 6. R Lesson 1.2 A E C 3. Brad and Katherine deposited $5000 in two separate accounts when their baby was born. Katherine's account earns compound interest at 4.87%, paid annually. Brad's account earns simple interest at 5.5%. The investments will mature when their child turns 20. Lesson 7. a