An open tank has a 3 m square horizontal section and weighs 3.5 kN. It contains water to a depth of 1.0 m. An unbalanced force of 15 kN is applied to the tank parallel to one of the pair of sides. Determine the minmimum height in meters of the tank in order to prevent any spillage.
a.1.24
b.1.60
c.1.76
d.1.50