( )。
A) If X'X, then X→X'.
B) If X→Y and Y'Y, then X→Y'.
C) If X→Y and X'X, then X'→Y.
D) If X→Y and Y→Z, then X→Z.
(65)Which function is used to lock a file in FoxPro DBMS? ( )。
A) FLOCK( ) B) RLOCK( ) C) LOCK( ) D)LOCK
(66)Which is NOT a characteristic of an RISC processor? ( )。
A) a high clock speed
B) a highly optimized pipeline
C) a few general-purpose registers
D) a limited amount of small instructions
(67) Local bus can reduce the occupation time of CPU. For the EISA local bus,
commonly the time can be reduced to( )。
A) 42% B) 22% C) 12% D) 2%
7
(68)In the modulation style of PSK ,if a kind of Modem's modulation rate is
3200baud and it's phase is 8 , what is the data transfer rate of this kind
of Modem ? ( )。
A) 14.4kbps B) 28.8kbps C) 9600bps D) 3200bps