2011 Sichuan Question 49 Single-choice Differentiating 2011_Sichuan卷 (英语) $47. If you want to use energy free, you have to_____.$ A. sign an agreement with the governmentB. pay around £14,000 for the equipmentC. sell the roof to some energy companiesD. keep the roof unchanged for within 25 years Answer keyD ☆ SaveCan't do it, show the explanation查看原卷 →