Figure X shows a closed rectangular tank of dimensions 42 cm by 42 cm by 70 cm with a cube of edge 23 cm glued to its bottom right corner. The tank contains 80 litres of water. Figure Y shows the same rectangular tank lying on its side. Find the height of the water level, in centimetres, corrected to 2 decimal places.

3 m

(3 m)

(3 m)