What can we add to brass to improve machining: A: Tin B: Copper C: Lead D: Manganese E: Carbon nanotubes

What is the primary abnormality in Wilson’s disease? A: Decreased excretion of copper in to bile B: Low serum of total copper C: Increased intestinal absorption of copper D: Reduced synthesis of ceruloplasmin

The world’s supplies of copper .

Delayed lead includes _________.? direct address lead|suspense lead|question lead|descriptive lead

‌What are the basic types of lead?‍‌‍ A: direct lead B: summary lead C: delayed lead D: question lead

1 p and 2 p coins are in copper color.

Metal utensils such as iron, copper, or aluminum are appropriate to prepare decoctions.

Data lead to conclusions; conclusions lead to recommendations.

Which of the followings indicates abnomal P-wave() A: P-wave is upright in lead Ⅱ B: P-wave is biphasic in lead Ⅲ. C: P-wave is inverted in lead av D: P-wave is not obvious in lead avVL E: P-wave is inverted in lead V5.

The main bearing shells are made of steel with a lining of bearing metal which may be white metal， copper-lead or aluminum-tin alloy What is the meaning of “which” in the sentence above?（）