Question $2$: Rock mass classification and rock failure criterion

$2\mathrm{.}1.$ A borehole produced the following lengths of core: $0\mathrm{.}9m,0\mathrm{.}6m,0\mathrm{.}3m,0\mathrm{.}8m,0\mathrm{.}3m,0\mathrm{.}09m,0\mathrm{.}07m,0\mathrm{.}08m,0\mathrm{.}2m,0\mathrm{.}05m,0,05m$ and $0\mathrm{.}3$ m $.$ Calculate the RQD of this rock assuming that there is no core loss.$(3)$

$2\mathrm{.}2.$ Describe the Q$-$System and its main components.

$(4)$

$2\mathrm{.}3.$ Assume a MRMR value of $72.$ Adjustment values are as provided below. Determine the Adjusted MRMR$.$

$(2)$

$\backslash$table$[[$Adjustment for,Adjustment value $(\%)],[$Mining induced stress,$100],[$Weathering$,75],[$Joint orientation,$69]]$

$2\mathrm{.}4.$ Name the two scenarios identified where the Hoek$-$Brown criterion would be applicable

$[10]$

$3$