Create the following SQL Queries

The database contains the following six tables:

coaches_season, each tuple of which describes the performance of one coach in one season;

teams, each tuple of which gives the basic information of a team;

players, each tuple of which gives the basic information of one player;

player_rs, each tuple of which gives the detailed performance of one player in one regular season;

player_rs_career, each tuple of which gives the detailed regular-season performance of one player in his career;

draft, each tuple of which shows the information of an NBA draft.

DBMS used is PostgreSQL

1. Find all the coaches who have coached exactly TWO teams. List their first names followed by their last names; 2. Find all the players who played in a Boston team or a Denver team. List their first names only.