18 (a) Clare invests $12 000 for 3 years at a rate of 8% per year compound interest. Calculate the value of her investment at the end of the 3 years. Give your answer correct to the nearest $10. $ ................................................. [3] (b) Zak invests $560 for one year. After one year his investment is worth $630. Calculate the percentage increase. ..............................................% [2] M SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW TON OD NIGRAM SIHT NI ETIRW