Logical conjunction of two binary decision diagrams

Compute a BDD for $B_{1} \wedge B_{2}$ by using an algorithm that applies dynamic programming. Document the execution of the algorithm by indicating pairs of BDDs $(q_{1},q_{2})$ and the BDD $q_{1} \wedge q_{2}$ computed by the algorithm. Suffice it to indicate only the effectively required pairs of BDDs. Furthermore, for an arbitrary BDD $B$ you can use the equations $B \wedge F=F$, $F \wedge B=F$, $B \wedge T=B$ and $T \wedge B=B$.

I manage to do the first steps, but then I fail, because I don't know how to find the terminal node (see question mark) and also because of the fact that $x_{2}$ does not exist in $B_{2}$:

$\text{T} \wedge \text{F} = \text{F}$
$\text{T} \wedge \text{T} = \text{T}$
$\text{F} \wedge \text{F} = \text{F}$