1. Intshayelelo yezinto zetsimbi yentsimbi luhlobo lwezixhobo zetsimbi ezingagqwaliyo, ikakhulu ezenziwe ngentsimbi, ichromium, i-nickel kunye nezinye izinto, ezineempawu ezintle zoomatshini, ukuqina, iplastikhi kunye nokumelana nokugqwala.Ifayile yechromium oxide...
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