Question

explain that liquid exerts pressure on the walls of a container with an activity

Answer 1

Take an example of an burst of water pipes in winter.In winter nights, as the atmospheric temperature is starts falling below 4 degree celcius  ,water in pipe line and it exerts large pressure on the walls of the water pipe lines hence cause them to burst.

Answer 2

Because in the gaseous state, the particles move about randomly at high speed. Due to this random movement, the particles hit each other and also the walls of the container. The pressure exerted by the gas is because of this force exerted by gas particles per unit area on the walls of the container.