1-73: Member B is subjected to a compressive force of 4 kN. If A and B are both made of wood and are 10 mm thick, determine to the nearest multiples of 5 mm the smallest dimension h of the horizontal segment so that it does not fail in shear. The average shear stress for the segment is Tallow = 2.1 MPa. 12 1-77. The wood specimen is subjected to the pull of 10 kN in a tension testing machine. If the allowable normal stress for the wood is ()allow 12 MPa and the allowable shear stress is allow 1.2 MPa, determine the required dimensions b and so that the specimen reaches these stresses simultaneously. The specimen has a width of 25 mm. B 4 KN 10 kN 10 kN