Questions & Answers of Shear stresses

A symmetric I-section (with width of each flange 50 mm,thickness of each flange = 10 mm,depth of web = 100 mm, and thickness of web =10 mm) of steel is subjected to a shear force of 100 kN. Find the magnitude of the shear stress(in N/mm2 the web at its junction with the top flange. __________