the invanpah solar power plant cost $2.2 billion to build. it was expected to generate one million megawatt hours of electricity a year at a price of $0.12 per kilowatt hours. (a megawatt is 1000 kilowatts). it has only produced 40% of that over the last year. if it maintains the same generation rate (40% of what was expected) for the next 30 years and the price of electricity rises to $0.15 per kilowatt hours after the 15th year, what will be it's payback, IRR, and NPV? the discount rate is 4% a year