Tooj liab yog cov ntshiab thiab ib qho hlau, txhua yam khoom ua los ntawm tooj liab qhia tib yam khoom. Ntawm qhov tod tes, tooj dag yog ib qho alloy ntawm tooj liab, zinc, thiab lwm yam hlau. Kev sib xyaw ua ke ntawm ntau yam hlau txhais tau hais tias tsis muaj ib txoj hauv kev tsis zoo los txheeb xyuas tag nrho cov tooj dag. Howev...
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