A man invested \(\$P\) in a certain bank at the rate of \(r\%\) per annum compounded annually. If the amount becomes \(1.44\) times of itself in \(n\) years, what is \(n?\)
1. \(r=20\%\)
2. At the same rate of interest the amount becomes \(1.728\) times itself in \(3\) years
OA D