A cuboidal water tank is 6 m long, 5 m wide and 4.5 m deep. How many litres of water can it hold?

A wooden bookshelf has external dimensions as follows : Height = 110 cm, Depth = 25 cm, Breadth = 85 cm (See Fig. 18.5). The thickness of the plank is 5 cm everywhere. The external faces are to be polished and the inner faces are to be painted. If the rate of polishing is 20 paise per cm² and the rate of painting is 10 paise per cm². Find the total expenses required for polishing and painting the surface of the bookshelf.

The paint in a certain container is sufficient to paint on area equal to 9.375 m². How many bricks of dimension 22.5 cm×10cm ×7.5 cm can be painted out of this container?

A cubical vessel is 10 m long and 8 m wide. How high must it be made to hold 380 cubic metres of a liquid?

Find the cost of digging a cuboidal pit 8 m long, 6 m broad and 3 m deep at the rate of Rs. 30 per m³.