单项选择题

牛顿力学第二定律方程形式为F=m（d2r／dt2），若以－t取代t代入方程中，方程的结果将完全不变。这意味着之一过程具有（）

A.退化性
B.进化性
C.不可逆性
D.时间反演对称性
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By the time the fire-engine arrived, the fire had been put _______ by the people thereA. downB. outC. offD. away
单项选择题
Review the definition of the phone_list view.CHEATE OR REPLACE ALGORITHM=MERGE DEFINER= ‘root‘@localhost‘ SQL SECURITY DEFINER VIEW ‘phone_list‘ AS SELECTe . id as id ‘e . first_name AS ‘first_name‘ ‘e . last_name AS ‘last_name‘ ‘coalesce ( ph1.phone_no, ‘ – ‘) AS ‘office_no‘ ‘coalesce (ph2 .phone_no, ‘ – ‘) AS ‘cell_no‘ FROM employees e LEFT JOIN employee_phone ph1 ON ph1.emp_id = E.id AND ph1.type = ‘office‘ LEFT JOIN employee_phone ph2 ON ph2 .emp_id = E.id AND ph2 .type = ‘mobile‘The tables employees and employee_phone are InnoDB tables;all columns are used in this view. The contents of the phone_list view are as follows: Mysql> select * from phone_list; 1 row in set (0.00 sec)Which method can you use to change the cell_no value to ‘555-8888‘ for John Doe?（）A.INSERT INTO employee_phone (emp_id, phone_no, type) VALUES (1, ‘555-8888‘,‘mobile‘)B.UPDATE phone_list SET cell_name ‘555-8888‘ WHERE first_name= ‘John‘ and last_name= ‘Doe‘C.DELETE FROM phone_list WHERE first_name= ‘John‘ and last_name= ‘Doe‘; INSERT INTO phone_list (first_name, last_name, office_no, cell_no) VALUES (‘John‘ , ‘Doe‘ , ‘x1234‘ , ‘555-8888)D.UPDATE employee_phone SET phone_no= ‘555-8888‘ where emp_id=1
A.CHEATE
B.phone_no,
C.phone_no,
D.emp_id
E.id
F.type
G.emp_id
H.id
I.type
J.00
K.INSERT
L.UPDATE
M.DELETE
N.UPDATE
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