1. Some aircraft component is fabricated from an aluminium alloy that has a plane strain fracture toughness of 40 MPa√m. It has been determined that the fracture results at a stress of 300 MPa when the maximum internal crack length is 4.0 mm. For this same component and alloy, will fracture occur at stress of 260 MPa when the maximum internal crack length is 6.0? Why or why not?