Problem $2(5$ marks$).$ A gate in the shape of a circular arc $($surface AB $)$ is depicted in Figure $2$ below, with

a radius $R=2m.$ The distance $DB=4m$ and the gate is $1$ m wide. The gate is impinged by water on one

side, while atmospheric pressure prevails on the other side of AB $($the same is true for the pressure above

the water $-$ it is atmospheric, too$).$ Determine the components of the fluid's force on surface $AB($in units

of kN $)$ and their locations. Also, calculate the resultant force $($in kN $)$ and its line of action $($these can be

expressed by the magnitude and an angle between its vector components$).$

Figure $2$: Hydrostatic forces acting on a circular arc shown as shape AB$.$