铰链四杆机构中，若最短杆与最长杆两杆长度之和大于其余两杆长度之和，则该机构一定是双摇

该文中共有八处错误, 每句中最多有两处, 错误涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏字符号(∧), 并在此符号下面写出该加的词。

删除：把多余的词用斜线（ ＼）划掉。

修改： 在错的词下划一横线, 并在该词下面写出修改后的词。

注意：1、每处错误及其修改均仅限一词；

2、只允许修改8处, 多者(从第9处起) 不计分。

I could never forget that accident. It was in the morning of February 8^th, 2011 that the accident happened. While sat in a restaurant on the Park Road, I saw an old man walking out of the City Park. Suddenly the yellow car was running fast along the 3^rd Street. Then it turns west into the Park Road. Just at that time the old man was crossing the Park Road. The old man had been knocked before the driver realized that had happened. The driver escaped, leaving the old man lying on the road. At the sight of this, I ran to him but saw that the number of the car was AC864. About two minutes late, I stopped a passing car and took her to the nearest hospital.

实验室制备甲酸铜晶体[Cu(HCOO)₂·4H₂O]的流程如下：

回答下列问题：

(1)小苏打水溶液显________性(填“酸”、“碱”或“中”)可治疗胃酸(0.2%～0.4%的盐酸)过多，反应的离子方程式为________________________。

(2)生成碱式碳酸铜[Cu₂(OH)₂CO₃]的离子方程式为________________________。

(3)操作a的名称是________，该操作使用的玻璃仪器有________。

(4)证明碱式碳酸铜已经洗涤充分的实验操作是________________________________。

(5)用无水乙醇洗涤晶体的目的是___________________________________。

一台水泵的功率是4.9kW，10min内它能将体积为 ______的水送到20m的高度．（g=10N/kg）

简述表面放射性污染的清除方法？

放射性物品道路运输装卸管理人员的主要职责是确保放射性物品一直处于其监管之下，防止丢失、被盗。