a) The initial embodied energy of a residential building in Wollongong is 3000 GJ. The operational energy use of the building is given in the table below. The annual recurring embodied energy in the materials required for maintenance of the building was found to add 1.5% to the initial embodied energy of the house. Determine the life cycle energy consumption of the building over 50 years in terms of kWh (1 year = 365 days). (5 marks) Table B1: Energy use information Fuel/Activity Gas/Space heating Electricity/Lighting Electricity/Space cooling Electricity/Cooking and hot water Energy Use 65 GJ/year 3 kWh/day 3500 kWh/year 1300 kWh/yeal b) The electricity cost in a retrofit building is expected to inflate at a rate of 7% per year and the electricity cost of the building in the first year is $400 (payable at the end of the year). The market discount rate is 10% per year. What is the present worth of the payment to be made at the end of the third year? (4 marks)