The difference between simple interest and compound interest on $1200 for one year at 10% per annum reckoned half-yearly is:	Choose the correct choice from the following.
A) $ 5 B) $ 8 C) $ 9 D) $ 3 E) $ 7

Rationale: "s . i = $ [ ( 1200 * 10 * 1 ) / 100 ] = $ 120 . c . i = $ [ 1200 * ( 1 + ( 5 / 100 ) ^ 2 ) - 1200 ] = $ 123 . difference = $ ( 123 - 120 ) = $ 3 . answer ( d )"
Answer: D