A cubical tank of edge 21 cm is filled with water up to $$\frac{1}{3}$$ of its height. Water from a tap is then piped into the tank at 1.5 litres a minute. (1 $$l$$ = 1000 cm³) <br> <input min="0" type="number" id ="imp5pg236q6_1" class="lineinput" placeholder="?" /> $$l$$ <input min="0" type="number" id ="imp5pg236q6_2" class="lineinput" placeholder="?" /> $$ml$$ of water is in the tank after 3 minutes.