Explanation:
On a hot day, the speed at which we perceived the smell of the perfume will be much faster due to the increase in kinetic energy of the perfume molecules.
Based on the kinetic molecular theory of gases, the average motion of particles increases as their thermal energy increases. On a hot day, the heat causes an increase in the average kinetic energy of the particles and the perfume molecules moves faster.
On a cold day, the molecules are slower and the rate at which we perceive the perfume smell is very slow. The particles will diffuse less faster and this is due to the low average kinetic energy they possess.