In 2005, suppose that Gilead Sciences, a leading pharmaceutical firm, was deciding whether or not to spend $90 million on R&D over the next 7 years on an AIDS drug. In 2005, their best estimate was that there was a 50% chance that R&D would be successful. They planned that if R&D were successful, then in 2012 they would invest $50 million in a manufacturing plant with zero resale value that would take 3 years to set up. Then in 2015 (given that they invested in the plant), variable cost of the drug would be $10/unit. There was a 50% chance that demand for the drug would be relatively high at 10 million units over its patent period and they would be able to charge $50/unit, and a 50% chance that demand would be relatively low at 5 million units and they would be able to charge $30/unit. The following is a visualization of the decision that Gilead Sciences had to make in 2005: Should Gilead Sciences go ahead with spending $90 million on R&D in 2005, given the beliefs about the future? Assume future payoffs are not discounted. Please show your work and reasoning to get full credit. Specifically