Using the equation P0​−P=ρ0​gz, we get:P=P0​−ρo​gz The pressure calculated by using this equation will be more than the actual pressure because density at a height of 10 km above Madras will be less than ρ0​.Yes, the answer will change if we also consider the variation in g. Because g decreases with height, it will have the same effect on pressure as that of density.