A sector gate is provided on a spillway as shown in the figure. Assuming g = 10 m/s², the resultant force per meter length (expressed in kN/m) on the gate will be __________

The porosity (n) and the degree of saturation (S) of a soil sample are 0.7 and 40%, respectively. In a 100 $$m^3$$ volume of the soil, the volume (expressed in $$m^3$$) of air is _____.

A concrete gravity dam section is shown in the figure. Assuming unit weight of water as 10$$kN/m^3$$ and unit weight of concrete as 24$$kN/m^3$$, the uplift force per unit length of the dam (expressed in kN/m) at PQ is____.

A reinforced concrete $$(RC)$$ beam with width of $$250$$ $$mm$$ and effective depth of $$400$$ $$mm$$ is reinforced with $$Fe415$$ steel. As per the provisions of $$IS$$ $$456$$ - $$2000,$$ the minimum and maximum amount of tensile reinforcement (expressed in $$m{m^2}$$ ) for the section are, respectively