Question $1[10$ marks$]$

Calculate the area$($s$)$ of reinforcement for an R$.$C beam with dimensions $600300mm,$ designed to resist a moment of $420kN.m,$ considering a yield strength $(fy)$ of $450$ MPa, concrete compressive strength$(f_{cu})$ of $25$MPa, and distance from compression face to compression reinforcement $(d^{\text{'}})$ of $40mm,$ with the distance from compression face to tension reinforcement $($d$)$ being $560mm.$