Prairie dogs are burrowing rodents. They do not suffocate in their burrows, because the effect of air speed on pressure creates sufficient air circulation. The animals maintain a difference in the shapes of two entrances to the burrow, and because of this difference, the air (rho = 1.29 kg/m3) blows past the openings at different speeds, as the drawing indicates. (vA = 7.2 m/s, and vB = 1.3 m/s.)

Assuming that the openings are at the same vertical level, find the difference in air pressure between the openings.

Indicate which way the air circulates.