A concrete beam with a rectangular section, $100mm$ wide and $300mm$ deep, is stressed by $3$ cables, each carrying an effective force of $240kN.$ The span of the beam is $10m.$ The first cable is parabolic with an eccentricity of $50mm$ below the centroidal axis at the center of span and $50mm$ above the centroidal axis at the supports. The second cable is parabolic which is concentric at the supports and has an eccentricity of $50mm$ below the centroidal axis at the center of span. The third cable is straight uniform eccentricity of $50mm$ below the centroidal axis. If the beam supports a uniformly distributed live load of $5k\frac{N}{m}$ and $Ec=38$GPa, estimate the instantaneous deflection considering Prestress $+$ self weight of the beam $(mm).$