Civil Engineering - UPSC Civil Service Exam Questions - Discussion

In a 4 m wide rectangular channel with 0.8 m depth of flow, a sharp-crested weir of 2.5 m length with its sill 0.3 m above the channel bed is fixed symmetrically across the width of the channel. Taking the flow to be free but with end contractions, what would be the discharge neglecting approach velocity effect? (Take C_d = 0.625)