The beam in the figure below is fabricated by attaching a C180x14.6 channel to a W250x17.9 shape with 15-mm-dia rivets at uniform spacing "s". The maximum shear force in the beam is 65 kN. Given properties: C180x14.6: A = 1850 mm^2; d = 178 mm; xcg= 13.8 mm Iy = 0.405x10^6 mm^4; tw 5.3 mm; tf = 9.3 mm W250x17.9: A = 2270 mm^2; d = 251 mm; I = 22.4x10^6 mm^4 tw = 4.8 mm; tf = 5.3 mm C180 x 14.6 W250 x 17.9 Calculate the moment of inertia of the built up section about the horizontal axis located 78.26 mm from the top. The answer is in x10^6 mm^4. 1. А. 36.76 В. 22.80 C. 27.46 D. 31.06 Determine the strength (kN) of the connection within spacing "s" based on rivet shear if the working stress for a rivet is 100 MPa. А. 140 2. В. 35.34 С. 180 D. 200 Determine the shear flow "q" (N/mm) that must be sustained by the rivets A. 243.72 3. В. 172.39 С. 191.02 D. 211.84 Find the maximum allowable spacing (mm) of the rivets if the working. А. 140 4. В. 160 С. 180 D. 200 What is the corresponding maximum bearing stress (MPa) exerted by the rivets? А. 245 5. В. 127 С. 222 D. 186 If the rivets are spaced 100 mm on centers, calculate the resulting bearing stress (MPa) in the members connected. А. 132 6. В. 138 C. 144 D. 150