The relation between the fraction of molecules $\left( \frac{N_E}{N_T} \right)$ and temperature is explained by the Boltzmann and Maxwell distribution graph.

(N/A) When the temperature is raised,the maximum of the curve moves to a higher energy value and the curve broadens out,i.e.,it spreads to the right such that there is a greater proportion of molecules with much higher energies.
Mole fraction and Temperature:
The area under the curve must be constant since the total probability must be one at all times. According to the figure,increasing the temperature of the substance increases the fraction of molecules that collide with energies greater than $E_a$. It is clear from the diagram that in the curve at $(t+10)$,the area showing the fraction of molecules having energy equal to or greater than the activation energy increases significantly,leading to an increase in the rate of reaction.