Types of Joins

What SQL would you write to get the average snowfall for all states?  Do not use aliases.  Only return states that gets snow.

What SQL would you write to get the average snowfall for all states – this time use aliases – “s” for the States table and “w” for the Snow table.

What SQL would you write to see which state all the presidents/other notables were born in?  No aliases!  Return state name, presidents place of birth and name. In that order :)

Again – with aliases!  “s” for States and “b” for BirthPlace