The figure shows an empty tank. It is made from two containers. The containers are in the form of 2 cubes of sides 8 cm and 20 cm respectively. The small container is attached to the centre of one of the sides of the big container. 4 litres of water is poured into the big container such that water flows in to fill part of the small container. What is the height of the water level in the big container ?
Round off your answer to two decimal places.