An onshore wind farm is being upgraded with more modern turbines. The original turbines have blades of length R R\,R and operate at an average wind speed of vvv. The upgraded turbines have blades of length 1.5R 1.5R\,1.5R and are located at a higher altitude where the average wind speed is 1.2v1.2v1.2v.
Assuming the air density is 10% lower at this higher altitude, and both types of turbines operate with the same efficiency, what is the ratio of the power output of an upgraded turbine to that of an original turbine?
2.332.332.33
2.922.922.92
3.503.503.50
3.893.893.89