Suppose that a wing component on an aircraft is fabricated from an aluminum alloy that has a plane strain fracture toughness of 29 MPam (26.39 ksivin.). It has been determined that fracture results at a stress of 109 MPa (15810 psi) when the maximum internal crack length is 8.1 mm (0.3189 in.). For this same component and alloy, compute the stress level at which fracture will occur for a critical internal crack length of 5.1 mm (0.2008 in.). i MPa