2. Let the complex numbers $z, w$ satisfy
$$
|z|=3,(z+\bar{w})(\bar{z}-w)=7+4 \mathrm{i} \text{, }
$$

where $\mathrm{i}$ is the imaginary unit, and $\bar{z}, \bar{w}$ are the conjugates of $z, w$ respectively. Then the modulus of $(z+2 \bar{w})(\bar{z}-2 w)$ is $\qquad$