Tham khảo tài liệu 'english skills - through pictures (phần 2) part 18', ngoại ngữ, anh ngữ phổ thông phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Keeping your mouth shut take your nose between your thumb and one finger so that you shut the air out and shut your breath in. How long can you hold your breath You will be wise if you do not try to hold it more than a minute. If oxygen is keptfrom a person for long he will become unconscious. When a person becomes unconscious through getting water or smoke in his lungs it is very important to start him breathing again. This is done by turning him face down putting something between his teeth to keep his mouth open and then working his lungs to start his breathing. hold koop from changing keep in ano placo keep from moving wise having knowledge and teeing what to do for the best unconscious not conscious having no sense or feeling or knowledge. will hold botd hold 367 The higher up we go the less is the pressure of the aữ because the weight of the aữ above US is less. As the pressure becomes less air gets thinner the amount of oxygen we get in one breath becomes less. We must take in more air to get the same amount of oxygen. KILIMANJARO - CAMSe y. EVEtEST AsleJ y ACONCAGUA S. Aoerlcol AORANOI New Zeotand MONT BLANC 4 Empe 28 000 12 000 4 000 SEA LEVEL The instrument we use to measure the pressure of the air is the barometer. Um prossoro on something the push on It. The olr Is pushing on thb boll putting pressure on It from all sides all the time. above over higher up. measure take the sseasuro of. 368 Men have been able 1953 to get to the top of the highest mountain in the world Mount Everest They had to use oxygen when they got up high. They had to keep control over the amount erf oxygen they used. They could get no more supplies from those below. This man who is going up a high mountain is using a supply of oxygen which is stored in those cans he is carrying on his back. By opening and shutting a valve he controls the amount of oxygen he breathes in. The gas has been pumped into the small space inside the cans. It is under pressure in
