With reference to wind turbines, which of the following statements are correct?
I. In a propeller-type turbine, the number of blades is three to six.
Il. The Darrieus type of turbine is an example of vertical axis turbines.
III. Propeller type turbines are rarely used.
IV. A multi-blade type turbine is an example of horizontal axis turbines.
1
II, III and IV
2
I, III and IV
3
I, II and IV
4
I, II and III