A container used for compressed air is made of Aluminium Alloy 2024. The required safety factor against yielding is 1.6 and the largest crack allowed through the thickness is 0.5cm. The form of the cracks gives a stress intensity modification factor of b = 1. (1) Find the stress intensity factor and the safety factor guarding against brittle failure. [3] (ii) If the material is changed to Aluminum Alloy 7075 and the crack remains the same, what will be the safety factor guarding against brittle fracture?