Design rectangular sections for the beams, loads, and values given. fy=50000psi, f'c=3000 span of l=28 ft, dead load not including beam weight = 3 k/ft, live load=3 k/ft, p*=0.5pb, concrete weights=150 lb/ft cubed, use h=d+2.5 inch, assume beam weight =10kN/m and phi=0.90