A horizontal axis drag type wind rotor, fitted with 4 thin rectangular blades having drag coefficient $1.29,$ is used to extract power when the average wind velocity in the rotor plane is $10 \mathrm{~km} \mathrm{~h}^{-1}$. The maximum power coefficient is

(A) 0.148

(B) 0.191

(C) 0.393

(D) 0.593

A horizontal axis drag type wind rotor, fitted with 4 thin rectangular blades having drag coefficient $1.29,$ is used to extract power when the average wind velocity in the rotor plane is $10 \mathrm{~km} \mathrm{~h}^{-1}$. The maximum power coefficient is

(A) 0.148

(B) 0.191

(C) 0.393

(D) 0.593

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