Question $3.$ Assuming $3-$layered soil within the $90cm$ rootzone depth, sampling of profile soil gave the following results$-$

$\backslash$table$[[$Depth $($in cm$),$Soil moisture $(\%$ by weight$),$Apparent Sp$.$ Gravity$],[0-30,15\mathrm{.}5,1\mathrm{.}4],[30-60,15\mathrm{.}5,1\mathrm{.}5],[60-90,18\mathrm{.}0,1\mathrm{.}6]]$

Calculate the total depth of water held in rootzone depth. If the field capacity of the soil is $22\%$ in all layers, calculate the amount of irrigation water $($in $cm)$ needed to bring the rootzone soil to field capacity.