A loop $ABCDEFA$ of straight edges has six corner points $A(0,0,0), B(5,0,0), C(5,5,0), D(0,5,0), E(0,5,5)$ and $F(0,0,5)$. The magnetic field in this region is $\vec { B } = (3 \hat { i } + 4 \hat { k }) T$. The quantity of flux through the loop $ABCDEFA$ (in Wb) is $\_\_\_\_$