In a hydraulic lift, compressed air exerts a force $$F$$ on a small piston of radius 3 cm . Due to this pressure the second piston of radius 5 cm lifts a load of 1875 kg . The value of $$F$$ is (Acceleration due to gravity $$=10 \mathrm{~ms}^{-2}$$)

In a $$U$$-shaped tube the radius of one limb is 2 mm and that of other limb is 4 mm . A liquid of surface tension $$0.03 \mathrm{~Nm}^{-1}$$, density $$1500 \mathrm{~kg} \mathrm{~m}^{-3}$$ and angle of contact zero is taken in the tube. The difference in the heights of the levels of the liquid in the two limbs is (Acceleration due to gravity $$=10 \mathrm{~ms}^{-2}$$)

A steady flow of a liquid of density $$\rho$$ is shown in figure. At point 1, the area of cross-section is $$2 A$$ and the speed of flow of liquid is $$\sqrt{2} \mathrm{~ms}^{-1}$$. At point 2 , the area of cross-section is $$A$$. Between the points 1 and 2, the pressure difference is $$100 \mathrm{~Nm}^{-2}$$ and the height difference is 10 cm . The value of $$\rho$$ is (Acceleration due to gravity $$=10 \mathrm{~ms}^{-2}$$)

Statement (A) When the temperature increases the viscosity of gases increases and the viscosity of liquids decreases.

Statement (B) Water does not wet an oily glass because cohesive force of oil is less than that of water.

Statement (C) A liquid will wet a surface of a solid, if the angle of contact is greater than $$90^{\circ}$$.