BVSS Prelim P1 CP

Bukit View Secondary School Secondary 4 Express Preliminary Examination 2024 BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SE CONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SE CONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VI EW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SE CONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SE CONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCH OOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW S ECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHOOL BUKIT VIEW SECONDARY SCHO OL SCHOOL CANDIDATE NAME CLASS INDEX NUMBER COMPUTING 7155/01 Paper 1 Written 23 August 2024 2 hours Candidates answer on the Question Paper. READ THESE INSTRUCTIONS FIRST Write your name, class and index number on the top of this page. Write in dark blue or black pen. You may use an HB pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, glue or correction fluid. Approved calculators are allowed. Answer all questions. The number of marks is given in brackets [ ] at the end of each question or part question. You should show all your working. The maximum number of marks is 80. For Examiner’s use Marks 80 Setter: Mrs Leong Wee Choo Parent's Signature:__________________ This question paper consists of 16 printed pages.

2 1 A computer stores data in bytes. (a) Convert the following binary integer into denary. 1100 1011 ………………………………………………………………………………… [1] (b) Describe how the denary number 298 is converted into hexadecimal. .…………………………………………………………………………………… .…………………………………………………………………………………… .…………………………………………………………………………………… .…………………………………………………………………………………… .…………………………………………………………………………………… .…………………………………………………………………………………… .…………………………………………………………………………………… .…………………………………………………………………………………… ………………………………………………………………………………… [3] (c) The MAC (Media Access Control) address of a device is shown below. Fill in the blanks below to indicate what the two groups of numbers represent. [2] (d) The IT manager is checking if the device in (c) had gained unauthorized access to the company’s network. Based on the log files of the network, the last 8 bits of the unauthorized device’s MAC address in binary form were identified to be 0111 0001. Explain clearly if the above device was the unauthorized device. .…………………………………………………………………………………… .…………………………………………………………………………………… ………………………………………………………………………………… [2]

3 2 Complete the table by writing the name of the most appropriate spreadsheet function for each description. Description Spreadsheet function Extract a substring starting from a particular position of a string Find the 3rd lowest value in a range Search the first column of a table for a specific value and output the data in the same row but in the next column Find out the sum of values in a range of cells based on the criteria applied to a different range Find out the number of empty cells in a range [5]

4 3 Four items of computer architecture and some descriptions are given. Draw a line to match the role of the item to its correct description. Items Arithmetic logic unit ● Address bus ● Output ● Memory ● Description ● Stores data and instructions so they can be quickly accessed by the processor ● Transports required information from processor to memory ● Intermediate or final results produced by the computer; usually in the form of processed data ● Processes data by performing basic mathematical and logical operations ● Transports required information between memory and processor ● S Stores data that will not be lost when power supply is interrupted ● Follows instructions and decides when data should be stored, received or transmitted [4]

5 4 (a) Complete the table by defining each of the threats to the privacy and security of data. Threat Definition Trojan horse ……………………………………………………………………. ……………………………………………………………………. ……………………………………………………………………. Worm ……………………………………………………………………. ……………………………………………………………………. ……………………………………………………………………. Pharming ……………………………………………………………………. ……………………………………………………………………. ……………………………………………………………………. [3] (b) More learning institutions are using technology. Describe one positive and one negative social or economic impact of using technology in education. Positive ………………………………………………………………………….. .…………………………………………………………………………………… .…………………………………………………………………………………… Negative ….……………………………………………………………………... .…………………………………………………………………………………… ………………………………………………………………………………… [2] (c) Define the term software piracy. .…………………………………………………………………………………… ………………………………………………………………………………… [1]

6 5 The following functions are written in pseudo-code. The function Check takes in a parameter Value and returns a Boolean. FUNCTION Check(Value) Valid = TRUE FOR Count = 0 to LEN(Value)-1 IF Value[Count] != '0' AND Value[Count] != '1' Valid = FALSE BREAK // BREAK exits loop ENDIF NEXT Count RETURN Valid ENDFUNCTION The function Success takes in a parameter Value and returns a Boolean. FUNCTION Success(Value) Total = 0 FOR Count = 0 to LEN(Value)-1 IF Value[Count] == '1' Total = Total + 1 ENDIF NEXT Count IF Total MOD 2 == 0 // MOD returns remainder RETURN TRUE ELSE RETURN FALSE ENDIF ENDFUNCTION The main program in pseudo-code is: Data = INPUT("Enter value")+'1' Result = Check(Data) IF Result == FALSE OUTPUT "Error" ELSE Result = Success(Data) IF Result == TRUE OUTPUT "No Error" ELSE OUTPUT "Error" ENDIF ENDIF The function LEN(Value) returns the length of Value.

7 (a) Describe the purpose of the variable Valid in the function Check. .…………………………………………………………………………………… .…………………………………………………………………………………… ………………………………………………………………………………… [2] (b) (i) Complete the trace table for the algorithm for the input data:1311 Main program Check() Success() Data Result Output Valid Count Value returned Total Value returned [2] (ii) Complete the trace table for the algorithm for the input data: 1001 Main program Check() Success() Data Result Output Valid Count Value returned Total Value returned [3]

8 (iii) The algorithm has been deployed for detecting errors in data transmission. Describe fully the purpose of the function Success and state the name of this error-checking method. Description …..…………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… ……………………………………………………………………………… Error-checking method ………………………………………………. [3] 6 A program written in Python needs to be translated using an interpreter. (a) Identify another translator. …………………………………