If the index of refraction of a medium is 1.4 determine the speed of light in that medium

Two wooden members of 80 × 120-mm uniform rectangular cross section are joined by the simple glued scarf splice shown. knowing that β = 22° and that the maximum allowable stresses in the joint are, respectively, 400 kpa in tension (perpendicular to the splice) and 690 kpa in shear (parallel to the splice), determine the largest centric load p that can be applied using mohr's circle. (round the final answer to two decimal places.)