Beyza weighs a water glass using a kitchen scale first when empty, then completely filled with water, and finally with some water in it. The results of these weighing operations in grams are shown below.
Accordingly, what fraction of the glass is full in the last weighing operation?
A) $\frac{1}{2}$
B) $\frac{2}{3}$
C) $\frac{3}{5}$
D) $\frac{4}{7}$
E) $\frac{5}{8}$