Show each possible different B$-$Tree that can be created with keys $3,7,10,12,13,$ and $15($with t$=2)($Hint: It is not a big number$)?$ For each one of them, give an example insertion order of these numbers that would result that tree. Remember that in a B$-$tree with t$=2,$ each node can have t$-1=1$ key minimum and $2$t$-1=3$ keys max. Also, if there are x keys in a node, it should also have x$+1$ children$/$branch $($with each child obeying the min$-$max key rule$).$