Subtract the amounts drank and given away from the initial amount. Express all fractions with a common denominator.<br><br>
&bull; Initial amount: \( 1\frac{1}{2} = \frac{3}{2} = \frac{30}{20} \) litres<br>
&bull; Drank: \( \frac{2}{5} = \frac{8}{20} \) litres<br>
&bull; Gave away: \( \frac{9}{20} \) litres<br>
&bull; Remaining = \( \frac{30}{20} - \frac{8}{20} - \frac{9}{20} = \frac{13}{20} \) litres<br><br>
Final Answer: A: \( \frac{13}{20} \) litres<br>
Check: \( \frac{8}{20} + \frac{9}{20} + \frac{13}{20} = \frac{30}{20} = 1\frac{1}{2} \). &check;