An advantage of aluminum pistons， when compared to cast iron pistons is （）.

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

The metal utensils made from iron, copper and aluminum are forbidden to decoct drugs.

Which of the following metals is environmental friendly? A: iron B: aluminum C: copper D: titanium

Mostconductingmaterialssuchascopper,aluminum,iron,nickel,andtungsten（）. A: increaseinresistancewithincreasedtemperature B: increaseinresistancewithdecreasedtemperature C: decreaseinresistancewithincreasedtemperature D: increaseinconductancewithincreasedtemperature

3.3The following materials are widely used in high power machines except for . A: Unalloyed iron B: Nd2Fe14B permanent magnetic materials C: Aluminum-iron alloys D: Silicon-iron

将以下段落翻译成中文：The cylinder head is bolted to the block. The manufacture casts the cylinder head in one piece from iron, from iron alloyed with other metals, or from aluminum alloy. Aluminum has the advantage of combining lightness with rather high heat conductivity.Depending on the style of engine, the cylinder head serves many functions.

Equal size balls of cork, lead, aluminum and steel are placed in water. Which one will float? A: Lead B: Cork C: Aluminum D: Steel

The main social services of the iron and steel industry system are the provision of iron and steel products and the consumption of iron ore A: 正确 B: 错误

1803a8273f88c11.png 的英文名称是______。 A: iron (II) carbonate B: ferrous carbonate C: iron carbonate D: ferric carbonate E: iron (III) carbonate