... 4.Labeling schemes help save energy. 7 UNIT 7 : READ /P.60, 611. a bulb : boùng ñeøn troønNEW WORDS: Toå chuyeân moân :Toå chuyeân moân : UNIT 7 : SAVING ENERGY ( READ) ... pay if she uses two energy -saving bulbs instead ?4.What is the purpose of the labeling scheme?5. Why should we save energy ? ANSWER THE QUESTIONS / P.61 7 UNIT 7 : READ /P.60, 61 5. efficiency ... money.2. We can use energy -saving bulbs instead of ordinary 100 watts bulbs to spend less on lighting.3. She will pay only US$ 2 for lighting if she uses two energy -saving bulbs instead.4....