The basic data for proportioning trial batches for normal weight concrete with an average compressive strength of $21$MPa at $28$ days are as follows :

Slump $=25-50mm$

Maximum aggregate size $=20mm$

SG of cement $=3\mathrm{.}15$

SG of coarse aggregate $=2\mathrm{.}74$

SG of fine aggregate $=2\mathrm{.}59$

water$-$cement ratio $=0\mathrm{.}68$

Water content $=190k\frac{g}{m}3$

Air Content of Concrete $=2\frac{1}{8}.$

Estimate the quantity of cement in $m^3$ if the volume of concrete needed is $8m^3.$

A$.0\mathrm{.}712$

C$.0\mathrm{.}636$

B$.0\mathrm{.}838$

D$.0\mathrm{.}969$

If the volume of dry coarse$-$grained aggregate is $0\mathrm{.}46\frac{m^3}{m^3},$ determine the weight of dry sand needed per cubic meter of concrete.

A$.5\mathrm{.}22kN$

C$.6\mathrm{.}52kN$

B$.5\mathrm{.}72kN$

D$.6\mathrm{.}12kN$

What is the total volume of cement, fine aggregate, water and air, if the weight of dry gravel is $13\mathrm{.}6k\frac{N}{m^3}.$

A$.0\mathrm{.}785m^3$

C$.0\mathrm{.}805m^3$

B$.0\mathrm{.}494m^3$

D$.0\mathrm{.}474m^3$