Answer
The bullet's speed is $336m/s$
Work Step by Step
The angular displacement between 2 bullet holes is $\Delta\theta=0.24rad$ and the angular speed is $\overline\omega=95rad/s$
$$\Delta t=\frac{\Delta\theta}{\overline\omega}=2.53\times10^{-3}s$$
$\Delta t$ is the amount of time it takes the bullet to fly from the left disk to the right one. Since the distance between them is $d=0.85m$, the bullet's speed is $$v=\frac{d}{\Delta t}=336m/s$$
