The Figure Shows a Graph of the Temperature of a Pure

Multiple Choice

The figure shows a graph of the temperature of a pure substance as a function of time as heat is added to it at a constant rate in a closed container. If $L F$ is the latent heat of fusion of this substance and $L V$ is its latent heat of vaporization, what is the value of the ratio $L V / L F ?$

A) 4.5
B) 7.2
C) 1.5
D) 3.5
E) 5.0