The 'Functional Unit' is an important part of conducting an LCA. What does the Functional Unit support in LCAs? What is the difference between social and technical definitions of risk and why are they important to engender trust in stakeholder deliberations. List 3 factors on how trust can be gained. Describe what an Input-Output Analysis is and indicate its main strengths and weakness. State and give a brief description of the four ethical principles of the Engineering Council