Which of the following pairs of variables X and Y will likely have a positive correlation?

(I) the speed of a wind turbine and the amount of energy it produces

(II) the price of gasoline and the demand for electric vehicles

(III) the speed of a car and the time it takes to reach a destination

a. I, II and III

b. II and III only

c. I only

d. II only

e. I and II only

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