Which two statements are true regarding B-tree indexs（）
AThe leaf blocks in the index are doubly linked.
BThe leaf node stores a bitmap for each key value.
CThe rows with NULL value in key columns also have entries in the index.
DThe deletion of a row from the table causes a logical deletion in index leaf block and the space becomesavailable for the new leaf entry
CPU中，除了内部总线和必要的寄存器外，主要的两大部件分别是运算器和（ ）。
A、控制器
B、存储器
C、Cache
D、编辑器
治疗肝硬化肝性脑病的措施是（）
A、休息，低盐饮食，限制入水量，补充蛋白质，给予利尿剂
B、休息，高热量高蛋白饮食，保肝治疗
C、休息，高热量限蛋白饮食，输入支链氨基酸
D、休息，禁食，积极补足血容量并采取止血措施
E、休息，控制输液量，纠正电解质紊乱，限制蛋白
Which of the following is the correct signal flow for an analog multi-room audio system？（）
A、Source，Volume Control，Speaker，Amp
B、Source，Amp，Volume Control，Speaker
C、Amp，Source，Volume Control，Speaker
D、Speaker，Amp，Volume Control，Source
Which of the following describes how to set the Read-only attribute on a folder？（）
ARight-click the folder > Properties > Security tab > select the username from the list > Permissions > clear the box labeled Read > OK
BOpen the folder > Tool > Folder Options > General tab > Read-only > OK
COpen the Command Prompt > type attrib r [drive：][path] > Enter
DOpen the Command Prompt > type attrib +r [drive：][path] > Enter
ERight-click the folder > Properties > General tab > Attributes > select Read-only > OK
Which of the following processor socket types would support an AMD processor?（）
AF
BLGA
C940
D775
E1155