adidasRivalry Field Socks, Multi-Sport Team Accessories Over-The-Calf, Men Women (2 Pairs)

Are there 2 pair of socks?

If I have a shoesize of 6 for US mens then what is my sock size?

Are these thick socks? It get really hot during play time, and I want to get some socks that aren't going to add to the heat.

Would the small fit a 9 yr old that wears size 4 youth