历年计算机等级考试四级二7,标签：计算机四级考试真题,计算机考试题库,http://www.dxs56.com
(68)Which traversal method for a binary tree does the following Pascal
code illustrate？(2 grades)
procedure traverse(p:pointer)；
begin 
if p《》nil
then begin
traverse(p↑。left)；
process(p)；
traverse(p↑。right)
end
end
A)lnorder B)Preorder C)Postorder D)Reorder
(69)What storage scheme does ＭＳ－ＤＯＳuse for storing
files on a disk？
A)l——nodes B)a linked list allocation
C)a continuous allocation D)a linked list with index
(70)Which of the followings is ＮＯＴa condition for deadlock？
A)Starvation B)Circular Wait
C)NO Preemption D)Mutual Exclusion
(71)Assume that an operating system uses a round——robin scheduler.The
process's quantum is 20 msec,and the context switch is 5 msec.What percentage of the 
context switch is 5 mesc.What percentage of the Ｃ
ＰＵ's time is spent on administrative overhead？(2 grades)
A)5％B)15％C)20％D)25％
(72)What state is a process in when it can't run because it needs a
resource to become available？(2 grades)
A)Ready B)lnterrupt C)Blocked D)Running
(73)The following sectors are requested from the disk:
11,1  ,36,16,34,9,12
What is the order of the sector reads if you are using the elevator
algorithm？(2 grades)
A)1,9,11,12,16,34,36 B)11,1,36,16,34,9,12
C)11,12,9,16,1,34,36 D)11,12,16,34,36,9,1
(74)What is the candidate key of a relational database？
A)A field with a constraint placed on it.
B)A set of fields that have no data in them.
C)A set of fields in a table used to identify a record uniquely.
D)Fields from multiple tables that are used for sorting records.
(75)What Normal From is the table shown in the exhibit？(2 grades)
┌──────────────────────┐
│┌──────────────────┐│
││emps tbl ││
│├──────────────────┤│
││emp_id ││
││emp_name ││
││emp_phone ││
││dept_name ││
││dept_phone ││
││dept_mgrname ││
│└──────────────────┘│
│(1)emp_id→emp_name,emp_phone,dept_name │
│(2)dept_name→dept_phone,dept_mgrname │
└──────────────────────┘
A)1NF B)2NF C)3NF D)BCNF
(76)Which operating system can Oracle database NOT be used in？
A)DOS B)UNIX C)Windows95 D)IBM Mainframes
(77)Which values are NOT permitted to be part of the primary key？
A)NULL B)punctuation 
C)special characters D)alpha——numeric characters
(78)Which phase of the software engineering process results in the
Software Requirements Specification？
A)definition phase B)engineering phase
C)maintenance phase D)development phase
(79)When drawing multilevel data flow chart of top——down,the balance
between parent chart and son chart must be taken into account,and to
pass judgment for the balance of the charts is regularly maintained by
(2 grades)
A)Output data B)Data dictionary
C)Processing number D)Input data
(80)Which is the strictest form of cohesion？
A)logical B)functional C)procedural D)coincidental
(81)Which is NOT a concept of White Box Testing？(2 grades)
A)You should execute all loops at their boundary conditions
B)You should execute all interfaces at their boundary conditions.
C)You sho  uld execute all logical decisions on their true and false
sides.
D)You should execute all independent paths within a module at
least once.
(82)Prototyping method is a dynamic design process,it requires people
who use prototyping method should have the following capability
A)Proficient program expertise
B)Immediately acquire requirement
C)Coordinate &organize eloquently
D)Handle tools smartly
(83)There are two styles in the evolution of instruction set ，that is
CISC and RISC.Which chip belongs to the RISC？
A)i APX 432 B)VAX——11/780 
C)Motorola 68000 D)Power PC 
(84)In advanced PC bus or local bus,which one has the fastest data
throughput？
A)ISA B)PCI C)MCA D)EISA