Understanding hydrostatic forces in water engineering is important, it helps civil engineers to calculate the forces exerted by water on water conveying struetures such as resenvoirs, canals and dams and analyse if the structure can withstand the pressure without failing or cracking. The table below shows data recorded at the laboratory during the investigation of hydrostatic forces on submerged surfaces.

$4\mathrm{.}1$ The data below was collected during the draining trial, complete all the missing data in the table.

$4\mathrm{.}2$ Analyse and interpret the resuiks of the collected data in relation to what was being investigated.

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