= Solution
The row player's unique <best response> to $L$ is $B$ and to $R$ is $T$. The column player's unique <best response> to $T$ is $R$ and to $B$ is $L$. Thus \b[the pure <Nash equilibria> are $(T,R)$ and $(B,L)$].
For a fully mixed equilibrium, let $p=\Pr(T)$ and $q=\Pr(L)$. Row-player indifference requires
$$
q+3(1-q)=6q+2(1-q),\qquad q=1/6.
$$
Column-player indifference requires
$$
3(1-p)=6p+2(1-p),\qquad p=1/7.
$$
Both <probabilities> lie strictly between zero and one, so these indifference conditions make both supported actions <best responses>. Hence the remaining equilibrium is
$$
\boxed{(\Pr(T),\Pr(B))=(1/7,6/7),\qquad(\Pr(L),\Pr(R))=(1/6,5/6).}
$$
Its <expected payoffs> are $(8/3,18/7)$. There are no other partly mixed equilibria: if either player is pure, the other's <best response> is unique, forcing both to be pure. If both mix, the displayed linear indifference equations uniquely determine their <probabilities>. The row player's equilibrium mixture differs from its maxmin mixture in part (a); these are different optimization criteria in this non-zero-sum game.
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