(a) Sachin invests \(\$7200\) at \(3\%\) simple interest per year. Find the total after 5 years. [3]

(b) A large rice packet has mass \(30\%\) greater than a small packet. The large packet is 650 g. Find the small packet mass. [2]

(c) Jenny starts with 4000 bacteria, increasing exponentially at \(r\%\) per day. After 6 days there are 4598 bacteria. Find r. [3]