A simply supported reinforced concrete beam has span of 8 m and is constructed from Grade 32 concrete. The beam is designed to carry a nominal dead load (including self-weight) of 20 kN/m and a nominal live load of 25 kN/m. The beam cross-section is shown in Figure 5a. (a) Determine the depth of neutral axis at the ultimate strength state, (8 marks) (b) Check if the beam is under-reinforced (4 marks) (c) Check if the beam is adequate to carry the design load. (8 marks) Figure 5a 400 WN28