甲乙两袋米，由甲袋倒出1/10到乙袋后，两袋米的重量相等，原来甲戴米比乙袋多（）
A. 80%
B. 10%
C. 20%
D. 25%
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水电解制氢、氧过程中，电解产生的氧气和氢气体积相等。
A. 正确
B. 错误
如果两变量间的相关系数r的绝对值位于0.7～1.0之间，可以认为它们之间的相关是（）
A. 中度相关
B. 低度相关
C. 高度相关
D. 无相关
一些贫困村已经脱贫了，若提前摘掉贫困地区的“帽子”，国家的扶贫政策就享受不了。所以，宁可“戴帽子”，在争取投资和项目上会有好处。
A. 正确
B. 错误
Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) DEPARTMENT_ID NUMBER SALARY NUMBER What is the correct syntax for an inline view? （）
A. SELECT a.last_name, a.salary, a.department_id, b.maxsal FROM employees a, (SELECT department_id, max(salary)maxsal FROM employees GROUP BY department_id) b WHERE a.department_id = b.department_id AND a.salary < b.maxsal;
B. SELECT a.last name, a.salary, a.department_id FROM employees a WHERE a.department_id IN (SELECT department_id FROM employees b GROUP BY department_id having salary = (SELECT max(salary) from employees))
C. SELECT a.last_name, a.salary, a.department_id FROM employees a WHERE a.salary = (SELECT max(salary) FROM employees b WHERE a.department _ id = b.department _ id);
D. SELECT a.last_name, a.salary, a.department_id FROM employees a WHERE (a.department_id, a.salary) IN (SELECT department_id, a.salary) IN (SELECT department_id max(salary) FROM employees b GROUP BY department_id ORDER BY department _ id)
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