Bài 15: Một con mèo ở trên cành cây cao 6,5m. Để bắt mèo xuống cần phải đặt thang sao cho đầu thang đạt độ cao đó, khi đó góc của thang với mặt đất là bao nhiêu độ? Biết chiếc thang dài 6,7m.

What do we mean when we speak of a calorie? Well, we know that the food we eat is (26) ……………… and provides heat. Some foods can provide much heat and other foods provide very little. The food that provide much heat provide many calories. We measure the amount of heat a food provides in calories, just as we measure your (27) …………… in inches or your weight in pounds. A calorie is a measure of the heat required to (28) …………… the temperature of one gram of water one degree centigrade. One calorie of food can also raise one pound of matter to a height of 40 inches. Two thousand calories a day of food in the body can provide a lot of heat and the (29) ……………. to do a lot of work.

26. A. burn B. burning C. burned D. to burn

27. A. height B. length C. width D. weight

28. A. produce B. raise C. lower D. change

29. A. function B. task C. right D. ability