The figure represents vertical sections of four wings moving horizontally in air. In which case is the force upwards?

Water is flowing with a velocity of $2 \ m/s$ in a horizontal pipe where the cross-sectional area is $2 \times 10^{-2} \ m^2$ at a pressure of $4 \times 10^4 \ Pa$. The pressure at a cross-section of area $0.01 \ m^2$ in Pascal will be:

According to Bernoulli's equation $\frac{P}{\rho g} + h + \frac{v^2}{2g} = \text{constant}$,the terms $\frac{P}{\rho g}$,$h$,and $\frac{v^2}{2g}$ are generally called respectively:

$A$ scent sprayer is based on

Rank in order, from highest to lowest, the liquid heights $h_a$ to $h_d$. The air flow is from left to right. The liquid columns are not drawn to scale.

$A$ wind with speed $50 \,m/s$ blows parallel to the roof of a house. The area of the roof is $300 \,m^2$. Assume that the pressure inside the house is atmospheric pressure. The density of air is $1.2 \,kg/m^3$. The magnitude of the force exerted by the wind on the roof will be: