QUESTION $2($PRESSURE SURVEYS$)$

$[17]$

$2\mathrm{.}1$ Briefly discuss the preliminary requirements for surveying an area.

$2\mathrm{.}2$ Describe the surveying procedure for a trailing hose method and state its advantages and disadvantages.

$2\mathrm{.}3$ Briefly discuss how natural ventilation pressure happens.

$2\mathrm{.}4$ With an aid of a diagram, illustrate and explain how ventilation in sub$-$level stoping method is achieved.