某些西方资产阶级史学家称鸦片战争为“通商战争”，认为这场战争是英国为维护正常贸易而进

旅游服务质量保证金担保期限届满前7个工作日，应续办担保手续。

小敏同学按以下步骤对她所用的牙膏进行探究：

【资料】牙膏中常用氢氧化铝、碳酸钙等物质作摩擦剂。

请回答：

⑴操作A是                   。

⑵从探究过程来看，你认为牙膏显               性。

⑶你认为用作牙膏摩擦剂的物质应具备什么特点呢？（回答一条即可）              。

If you go to Brisbane, Australia, you can easily get a small book called Discover Brisbane free．Here is something about banks on page 49:

ANZ Banking Group

Cnr．Greek & Queen Sts ………………………………………………238 3228

Bank of New Zealand

410 Queen Street  …………………………………………………… 221 0411

Bank of Queensland

229 Elizabeth Street ………………………………………………… 229 3122

Commonwealth Banking Group

240 Queen Street …………………………………………………… 237 3111

National Australia Bank Ltd

225 Adelaide Street ………………………………………………… 221 6422

Westpac Banking Corp

260 Queen Street …………………………………………………… 227 2666

Banking hours are Mon.-Thu．9:30 am to 4 pm．Fri．9:30 am to 5 pm．All banks close Sat．Sun．& Public Holidays.

小题1:You can find ANZ Banking Group on ________________.

A．Queen Street

B．Elizabeth Street

C．the corner of Greek Street and Queen Street

D．the corner of Queen Street and Elizabeth Street小题2:On Saturdays, you can go to _____________ to put your money in or take your money out.

A．ANZ Banking Group

B．Bank of Queensland

C．National Australia Bank Ltd

D．none of the banks小题3:In Australia, the banks have their longest service hours on _____________.

A．public holidays

B．Fridays

C．Saturdays

D．Sundays

已知H₂、C₂H₄、C₂H₆各1mol分别燃烧生成液态水，放出热量分别为285.8kJ、1409.5kJ、1558kJ．试写出C₂H₄生成C₂H₆的热化学方程式．

砌筑砂浆含水率测定值之差超过（）此组试验结果为无效.

A.1.5%

B.2%

C.2.5%

D.3%