The roof of the house is in the shape of a square with a side of 4 meters. with what force

The roof of the house is in the shape of a square with a side of 4 meters. with what force the air presses on the kysh at an atmospheric pressure of 770 mm Hg

a = 4 m.
h = 770 mm = 0.77 m.
ρ = 13545 kg / m ^ 3.
g = 9.8 m / s ^ 2.
F -?
p = F / S.
F = p * S.
p = ρ * g * h.
Since the shape of the roof is square, then S = a ^ 2.
F = ρ * g * h * a ^ 2.
F = 13545 kg / m ^ 3 * 9.8 m / s ^ 2 * 0.77 m * (4 m) ^ 2 = 1635369 N.
Answer: the air presses on the roof with a force of F = 1635369 N.