Now my questions:

**How do I write the relation between set {1} and set (3,4)?****How do I write the relation between (1,3) and (3,4)?****Does the above notation only hold for ordered sets, or also for unordered sets like {a,b}<<{c,d}, where a>b or a<b and c>d or c<d?**

Looking forward to hearing your answers.

Best,

Thomas