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More Mining Engineering Questions
The width of manhole not less than . . . . . . . . m.
The whole circle bearings of two lines are 80°and 300°.The interior angle included between two lines is . . . . . . . .
Brattice cloth used in under ground should be . . . . . . . .
Forcing fan requires air lock at . . . . . . . . shaft.
A Roadheader district produces 20 mg/m 3 of airborne dust with the following size distribution: Size up to Cumulative wt% 1 μm 1 5 μm 5 10 μm 10 20μm 20 50μm 50 >50μm 100 The concentration of respirable fraction of dust in mg/m 3 is