COMPUTING

.
1.
A Scottish bank developed software to enable customers to use their mobile phones
to check balances, transfer funds, pay bills and pay for goods. The bank employed
a software development company at the beginning of the project.
(
a
) The software development company considered whether to deliver the
proposed services using the browser software already available on mobile
phones or to create an application. The application was to be downloaded
from the bank’s website onto the mobile phone.
(i) State
two
types of
feasibility
that would have been considered when
making this choice.
(ii) Explain why each of your answers to (i) is relevant in this situation.
(
b
) After the feasibility study, a
project plan
was created.
State
two
elements of a project plan and explain why each is used.
(
c
) An
operational requirements document
was produced.
(i) State
one
benefit of this document for the bank.
(ii) State
one
benefit of this document for the software development
company.
(iii) Describe how the operational requirements document would have been
used at the evaluation stage of the software development process.
(
d
) During the testing stage of the software development process a
summary of
results
was produced. Describe how the summary of test results would be of
benefit during maintenance.
(
e
) The software development company made use of
CASE
tools.
State
one
benefit of using CASE tools.

2.
A teacher is writing a program to deliver a computerised version of a multiple
choice test. The test has twenty questions and each correct response is awarded
one mark. An incorrect response is awarded zero marks.
The test is in a text file. Each question in the text file has a stem, four possible
responses and the correct answer.
Here is part of the text file showing two of the twenty questions:
(
a
) The teacher decides to create a
record
data structure for each question.
(i) Describe what is meant by a record data structure.
(ii) Define a suitable record for a question.
(iii) Declare a variable that can store the twenty questions.
(
b
) When running the program an error occurs when reading the file.
(i) State
one
example of a run-time error that could occur when reading
the text file.
(ii) Describe
one
feature of a software development environment used to
identify where in the program the run-time error occurred.
(
c
) When taking the test, a pupil’s twenty responses are stored in a 1-D array
called
responses
.
Write an algorithm, using detailed pseudocode, which will calculate the
pupil’s total for the test.
Your answer should refer to the variable defined in (
a
)
Stem
Which of the following is a suitable file
format to use for a photograph?
Which malicious software self-replicates
without a host file?
Choice A
RTF
Choice B
JPEG
Choice D
MP3
Answer
JPEG
Virus Trojan Spam Worm
responses
JPEG
Worm
Choice C
CSV
Worm

3.
A salesperson is given a list of six locations that he must visit. His IT department
has given him a program to plan his journeys. He enters the locations into the
program and it calculates the distances of each location from his house. The
distances are displayed as shown below:
(
a
) The program has an option to sort the distances. The program uses the
simple sort
algorithm.
(i) Explain how the
simple sort
algorithm sorts a list into ascending order.
(ii) State
two
swaps that will take place during the first pass through the
list.
(iii) State the number of comparisons that took place on this first pass.
(iv) Calculate the total number of comparisons that will take place to
complete the simple sort for the distances. Show your working.
Journey Planner
Distances
Locations
Reverse
Sort
Edinburgh
Hawick
Crieff
Dumfries
Carluke
Prestwick

SECTION I (continued)
3. (continued)
(
b
) The distances after sorting are held in a 1-D array as shown.
The button marked
Reverse
becomes active once the list has been sorted. It
is intended to reverse the order of the list from highest to lowest or vice versa
but this feature does not work. He asks the IT department to correct it. The
incorrect algorithm used is shown below:
1 set lower to lowest index
2 set upper to highest index
3 for counter=lower to upper
4 temp=distance[counter]
5 distance[counter]=distance[upper–counter]
6 distance[upper–counter]=temp
7 end for
(i) The distances in the 1-D array have been used with the section of code
shown above to partially complete a trace table. State the missing
values at positions A, B, C, D and E for the first pass through the loop.
(ii) The last pass through the loop has the effect of undoing the first pass.
Explain how the algorithm can be corrected.
(iii) The order of the list could have been reversed using the simple sort
algorithm. Explain why the corrected algorithm is more efficient.
Index
0
1
2
3
4
5
Distance
3
40
42
59
84
137
Line
No
lower
upper
counter
temp
upper–counter
distance[counter]
distance[upper–counter]