CAPE Computer Science Unit 2 · 2010 · Paper 2

37 questions and parts from this paper. Open one to see it in full, then practise it on Quelpr and get it marked against the mark scheme.

1. 1(a)2 marksDefine the term abstract data type (ADT).
2. 1(b)(i)1 markGive an ADT operation that can be used to store an element in a singly linked list.
3. 1(b)(ii)3 marksA singly linked list is created and elements 25, 50, 75 are placed in that order. Draw the list after all three elements have been placed using the operation from (b)(i), clearly indicating the beginning and end of the…
4. 1(c)(i)4 marksThe Queue ADT provides enqueue(Queue, data) and dequeue(Queue) operations. Suppose a Queue must be implemented for storing integers. Describe the computer storage used for implementing the queue operations.
5. 1(c)(ii)5 marksWrite C code for a function that implements enqueue(Queue, data) assuming data is an integer, handling queue overflow conditions.
6. 1(d)6 marksGiven a queue q with elements, and stack stk with operations pop, push, and isEmpty, write an algorithm to reverse the order of all elements in q using only Stack and Queue ADT operations.
7. 1(e)4 marksExplain how Stack ADT operations are implemented if a singly linked list is used.
8. 2(a)(i)10 marksDescribe how the selection sort algorithm works to sort a set of 10 integers in ascending order.
9. 2(a)(ii)3 marksDraw the array after the first, second, and third passes of the selection sort algorithm (three diagrams in all).
10. 2(b)10 marksA one-dimensional array num contains 20 unsorted integers. Write C code to accept an integer target from the user, search for it in num, print the location if found, or print an appropriate error message if not present.
11. 2(c)2 marksState when binary search should be used on an array.
12. 3(a)4 marksMaintainability is a critical attribute of a well-engineered software product. Briefly discuss TWO other attributes of well-engineered software.
13. 3(b)4 marksExplain, giving TWO reasons, why it is important to involve end users and management in the development of a software product.
14. 3(c)3 marksExplain why a software system used in a real-world environment must be upgraded or become progressively less useful.
15. 3(d)14 marksDraw a Level-0 data flow diagram representing the described hiring process of an organisation.
16. 4(a)(i)2 marksState TWO reasons why a feasibility study is undertaken.
17. 4(a)(ii)3 marksDescribe the contents of the requirements specification document.
18. 4(b)14 marksDraw an entity-relationship model for the described organisation scenario involving departments, employees, skills, projects, and tasks.
19. 4(c)6 marksConsider a linear search function lsearch(arr, n, key) returning the index of key or -1. Briefly describe THREE tests which can be used to determine if lsearch is working correctly.
20. 5(a)(i)6 marksDraw a diagram showing the layers of the OSI model for computer communication.
21. 5(a)(ii)6 marksDescribe the role of EACH of the top THREE layers of the OSI model drawn in 5(a)(i).
22. 5(b)4 marksWhat is meant by a 'page fault' in an operating system that uses paging, and how is it handled?
23. 5(c)6 marksState and describe TWO applications that use or can use GPRS.
24. 5(d)3 marksIn an operating system, explain what can cause a process to move from the running state to the ready state.
25. 6(a)3 marksComplete the labelling of the diagram by giving the names of A, B and C.
26. 6(b)2 marksState, giving a reason, which network topology is being employed.
27. 6(c)2 marksGive ONE disadvantage of the topology identified in (b).
28. 6(d)1 markList ONE device which is NOT shown in the diagram that may also be found on the network.
29. 6(e)3 marksBriefly describe the function of the firewall.
30. 6(f)1 markState the meaning of the abbreviation ISP.
31. 6(g)1 markState what service the company would likely use from the ISP.
32. 6(h)1 markIf the company had an Intranet, state on what protocol it would be running.
33. 6(i)3 marksDifferentiate between a peer-to-peer and a client server configuration.
34. 6(j)2 marksGive ONE disadvantage of a client server configuration.
35. 6(k)(i)2 marksDescribe ONE function of modern operating systems.
36. 6(k)(ii)2 marksState the difference between the type of operating system running on A and that running on B.
37. 6(k)(iii)2 marksGive ONE method used to secure files.