1 Read the text below. replace verb Human Body Energy Human body is actually a living machine and is like all other machines. This living machine needs fuel to supply it with energy. The fuel is provided by the food which we eat. However, do we know how much we need to stay healthy? The energy value of food is usually measured in calories. A calorie is the amount of heat which is required to raise the temperature of 1 kg of water by 1 degree C. The number of calories which people need per day varies. It depends on the activity which the people are involved in. For example, people will need more calories for standing than for sitting, people need more for running than for walking, etc. The energy which is provided by food is in the form of three kinds of chemical substances. They are carbohydrate, protein and fat. Carbohydrate provides 8.8 calories per gram (cal/gm) of energy, protein 4.0 cal/gm and fat 8.0 cal/gm. Each food contains different proportion of these substances. These three chemical substances are all important for body staying healthy. Source: freeenglishcourse.info nouse'is.... l" is..... 2. Answer the following questions based on the text above.1. What does the text explain about the human body?
2. What is a calorie?
3. How many calories do the people need in a day?
4. Where can we find the calories needed by our body?
5. Do the runners and the office workers need the same number of calories?
6. Name three chemical substances that are all important for body staying healthy.
7. "it depends on the activity which people are involved in" . what does the word "it" in the sentence refer to? ​