A triangular truss structure is shown below. If all truss members are 2.0 m long (a, b, & c in the sketch) and forces L and Rare both 8.0 kN, then what is the force in truss member a? Assume that the three forces L, R, and S have vertical lines-of-action. Your answer should be in kN. Only enter the number, not the units. a S 2