The base of a water fountain tank in garden is shown in figure. The corners are right angles. There is water to a depth of $40 \mathrm{cm}$ in a tank. The quantity of the water in the tank is $k {\mathrm{m}}^3$, then the value of $k=?$

 

The base of concrete platform in the play field is shown in figure. All corners are right angles and all measures are in meters. If the height of the platform is $2 \mathrm{m}$, if the volume of concrete used for constructing it is equal to $k m^3$.