Estimate the mass of the earth’s troposphere using the following assumptions, being mindful of units. (1) the earth is a smooth sphere of radius 6000 km. (2) the troposphere’s mass density varies linearly from 1 kg m − 3 at the earth’s surface to 1 /3 kg m − 3 at the top of the troposphere and is not a function of latitude or longitude. (3) the troposphere occupies the first 11 km of the atmosphere above the earth’s surface.(a) estimate the mass of the earth's troposphere, based on the above assumptions. (b) again, to put this into perspective, assume the layer of air in the troposphere were to be replaced by a layer of water with the same total mass. how deep would the layer of water need to be? as usual here, assume that the mass density of water, δ, is 1000 kg/m3.