Problem $1$: A rainfall record contains $32$ years of measurements at $5-$minute intervals. The maximum rainfall amounts for intervals of $5$ min, $10$ min, $15$ min, $20$ min, $25$ min and $30$ min have been calculated and ranked. The top three rainfall amounts, in mm$,$ for each time increment are given below. Calculate the IDF curves for return periods of $10$ and $100$ years