以下哪个公式为计算活动历史提供了最精确的结果（）？

A、AD=工作数量/生产速率

B、AD=工作数量/资源的数量

C、AD=工作数量/工作数量

D、AD=（生产速率×工作数量）/资源的数量

国家支持企业、研究机构、高等学校、网络相关行业组织参与网络安全国家标准、（）的制定。

A、 行业标准

B、 行业

C、 行业准则

D、 标准

The validate_password plugin is loaded and displays the following settings in global variables: Mysql＞ SHOW VARIABLES LIKE ‘validate_password%’; When attempting to set your password, you get the following error: Mysql＞ SET PASSWORD = PASSWORD (‘Hoverl@%’); ERROR 1819 (HY000): Your password does not satisfy the current policy requirements What is the cause of the error?（）

A、 The password is eight characters long, but needs to exceed validate_password_length to be valid

B、 All of the MEDIUM password policy requirements have not been honored

C、 The password matches a substring Hover as a dictionary word

D、 The password does not match the validate_passoword_number_count requirement

E、 There is no dictionary file defined, so password validation cannot work as expected

The following commands are available in the Linux binary distributions of Mysql: Mysqld Mysqld_safe Mysql.server What is the correct description of each of these commands?（）

A、 A

B、 B

C、 C

D、 D

Given the set of routers, each with an interface on the same multi-access network: Which router can never be a designated router on that multi-access network?（）

A、 RouterA

B、 RouterB

C、 RouterC

D、 RouterD

Which three statements are characteristic of the MEMORY storage engine?（）

It can support transactions

Table contents are not saved if the server is restarted

It cannot contain text or BLOB columns

It can support foreign keys

Each table is represented on disk as an.frm file

Each table has a corresponding.MYI and .MYD file