B. Fig. 2.
[Diagram including points T, T', T''; bands B, B'; and ray L.]
When connected to 2 tacks T' and T'' by 2 bands B and B'.
Answer: Along L, the bisector of T' and TTT''.
C. Fig. 3.
[Diagram including points T, T', T''; band B; and ray L.]
The same as B, but only 1 band B.
Answer same as to B.
D. Fig. 4.
[Diagram including points T, T#1#, T', T''; and ray L.]
When connected to 3 tacks by any number of bands.
Draw T'T#1#, and treat as in B and C.