In an opencast coal mine, blast vibrations are measured at two locations, A and B simultaneously for a maximum charge per delay (Q) of 1200 kg as given.

Assume the relation

$PPV = K \left( \frac{D}{\sqrt{Q}} \right)^{-\beta}$

where, $K$ and $\beta$ are site constants. The PPV in mm/s, at a distance of 200 m from the blast face, is _____. (round off up to 2 decimals)