Question $1$: Basic theory & definitions of rock mechanics

$1\mathrm{.}1.$ Define and differentiate between virgin stress, resultant stress, and induced stress in the context of underground rock masses

$1\mathrm{.}2.$ Calculate the Induced stress for a mining operation at $3050$ m depth, $2800k\frac{g}{m^3}$ density and resultant stress of $93$ MPa

$1\mathrm{.}3.$ If the ratio of horizontal to vertical virgin stress in Question $1\mathrm{.}2$ is $0\mathrm{.}7,$ calculate the virgin horizontal stress

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