How do I completely solve this problem? I have created truth tables for a↓b and a|b but I don't understand the rest of the question.

Here it is:

Connectives ↓ (Pierces's arrow, nor) and | (Scheffer's stroke, nand) are defined by a↓b := 7(a v b), and a|b := 7(a ^b). Express each of these connectives in terms of 0 and →. Construct truth tables for ↓ and |. Show that each of the connectives 7, ^ and v can be expressed in terms of the connective ↓, and in terms of the connective |.

*the 7 is to negate....