$3\mathrm{.}38$ Answer question $3\mathrm{.}35,$ but use a join using JOIN ON syntax. What are the consequences of using $($or not using$)$ the DISTINCT keyword in this version of the query?

$3\mathrm{.}39$ Answer question $3\mathrm{.}36,$ but use a join using JOIN ON syntax. What are the consequences of using $($or not using$)$ the DISTINCT keyword in this version of the query?

$3\mathrm{.}40$ Answer part $(4)$ of question $3\mathrm{.}37,$ but use joins using JOIN ON syntax. What are the consequences of using $($or not using$)$ the DISTINCT keyword in this version of the query?