（1）下图为电解水的装置，据实验的有关现象回答：
①A为电源的_____极，（填正或负）。
②如D管中产生气体的质量是16克，则C管中产生气体的质量为_____克。
（2）小雨收集到一瓶浑浊的河水，他要模拟自来水厂的净水过程，最终制成蒸馏水。其实验过程如下所示。请回答以下问题。
①A物质的名称是 ，操作①的名称是 ；
②操作②过程主要是 变化（填“物理”或“化学”）；
③小雨取少量液体D于试管中，加入少量肥皂水，振荡，发现有较多浮渣产生，说明液体D是 水。 (填“硬”或“软”)
⑴ ① 负 ② 2
⑵ ① 明矾；过滤 ② 物理 ③ 硬
上海进出口贸易公司(SHANGHAI IMPORT AND EXPORT CO.LTD.)于2007年3月1日与澳大利亚客户MANDARS IMPORTS Co.Ltd.签定一份订购合同。内容如下：
PURCHASE CONTRACT
P/C N0.：070101
DATE：MAR.1[st]，07
THE SELLER： THE BUYER：
Shanghai Import and Export Co.Ltd． Mandars Imports Co.Ltd．
Address：No.1321 Zhongshan Road． 38 Queensway.2008
NSW Australia
Shanghai，China
We hereby confirm having sold to you the following goods on terms and conditions as stipulated bellows：
Description of goods：
Ladies Denim Skirt
Exactly like Artwork，but change the main label position to center back and cancel the zipper．
Fabric：
99% cotton 1%Elastic Construction：11×16+70D/88×46
Washing：
blue-grey like our sample no．MA212090
Changing：
Please put the Mandars hangtag not in center back，but in seam．
Please print at the back side of the
care label：
Product from Mandars 2008 NSW/AUSTRALIA
Packing：
Flat pack without folding 6 pieces assorted sizes per polybag，3 polybags in a master polybag and then into an export carton．
Maximum sizes of export cartons：
Length WidthHeight
60 42 variable
Color：Blue/grey
Marking of the cartons：
As per our information
Hangtag：MANDARS
Main label：MANDARS
Care label：
With correct Composition&washing instruction
Samples：
Counter samples：3 pieces in size 38 ex Shanghai 2007.3.15
Samples：
2 pieces in size 38 ex Shanghai 2007.4.20
Pre-production samples：
The Pre-production samples should be made after the fabric haVe been tested and passed by ITS Shanghai Branch，
Then will be sent to customers’quality assurance department．"Go" for production can only be given after their approval．
Payment：
By confirmed and irrevocable L/C payable by beneficiary’s drafts at 60 days after B/L date sight and remain valid in China for further 16 days after shipment．
Price Terms：
AUD7.00 per piece FOB Shanghai
Quantity：
18000 pieces
Amount：
AUD126000.00
Delivery Date：
2007.5.30Ex Shanghai by sea/Maersk
To Sydney，Australia with partial and transshipment allowed
Delivery Address：
Mandars Imp.Co.
Atm：Ken
Shipping agent：
National Containers Ltd
Size and color assortment．
1 size | 36 | 38 | 40 | 42 | Total |
1 Blue grey | 3000 | 6000 | 6000 | 3000 | 18000 |
Denim skirt with lace | 36 | 38 | 40 | 42 |
A．waist | 36 | 38 | 40 | 42 |
B．waist height | 4 | 4 | 4 | 4 |
C．hip，18 cm incl.waistband，straight | 47 | 49 | 51 | 53 |
D．bottom complete round measured | 209 | 213 | 217 | 221 |
E．1ength at CF | 58 | 58 | 58 | 58 |
F．back length at CB | 60 | 60 | 60 | 60 |
| 合同规定何种支付方式，具体内容如何 |