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ead of motion, as in a pressed spring. 20. Inanic pounds are substances containing two or more elements that are not animal or vegetable. Most inanic pounds do not contain carbon and are derived from mineral sources. 21. A horseshoe mag is a piece of ironattracting metal in a shape of letter U. 22. Stainless steel is a type of steel that does not rust. 23. A medical thermometer is an instruments used for measuring the temperature of a patient. 24. A suspension bridge is a bridge that is hung from strong steel roupes fixed to towers.