derive a formula for the time t that it will take for the perfume molecules to diffuse a distance l into the room. you can assume that the mass m and collision cross-section σ of the molecules of perfume are roughly the same as those of air molecules; that is, you can assume that m is the same for the perfume, o2, and n2, and likewise for σ. hint: the answer will depend on l, m, σ, the pressure p, the temperature t.