Study the following passage carefully and answer the questions.

Wind is an inexhaustible source of energy and aerogenerator can convert it into electricity. Through not much has

so far been done in this field, the survey shows that there is a vast potential for developing wind as an alternative 

source of energy. The wind survey has four components -- direction, duration, speed and distribution.

On this basis U P. hill areas have been found an ideal place for setting up aerogenerators. In U.P. hills alone, as 

many as 58 sites have been identified.