2022 MSHS Sec 4 Computing SA2 Paper 2 MS

Thumb drive No: STL Class/ Index Number / Centre Number/ ‘O’ Level Index Number / Name MARIS STELLA HIGH SCHOOL PRELIMINARY EXAMINATION SECONDARY FOUR COMPUTING 7155/02 Paper 2 Practical (Lab-based) 26 August 2022 2 hours 30 mins Additional Materials: Electronic version of LIBRARY.XLSX file Electronic version of NUMBER.PY file Electronic version of WORD.PY file Electronic version of CONVERTER.PY file Insert Quick Reference for Python READ THESE INSTRUCTIONS FIRST MARK SCHEME For Examiner’s Use This document consists of 10 printed pages. 50

2 Task 1 Question Answer Marks 1 =LEFT(VLOOKUP(D5, $A$28:$B$40, 2, FALSE),6) & A5 2 marks: VLOOKUP 1 mark: LEFT 3 Question Answer Marks 2 =G5-F5 1 Question Answer Marks 3 =IF(H5>21, "Overdue", "Not Overdue") Minus 1 mark if message is of wrong spelling/case 2 Question Answer Marks 4 =COUNTA(A5:A21) 1 Question Answer Marks 5 =COUNTIF(J5:J21, "Overdue") 1 Question Answer Marks 6 =AND(I5="Yes",J5="Overdue") 2

3 Task 2 Quest ion Answer Marks 7 total = int(input('Enter total numbers to input: ')) #6a for count in range(total): 2 8 while number < 1 or number > 100: #6b range check number = int(input('Out of range, please re-enter a positive integer: ')) 2 9 total = int(input('Enter total numbers to input: ')) highlist = [] #6c for count in range(total): number = int(input('Enter a positive integer: ')) while number < 1 or number > 100: #6b range check number = int(input('Out of range, please re-enter a positive integer: ')) if number >= 1 and number <= 40: print(number, '- Low') elif number > 40 and number <= 70: print(number, '- Medium') elif number > 70 and number <= 100: print(number, '- High') highlist.append(number) #6c print("The numbers classified as high are: ", highlist) #6c 3 10 allnumbers = 0 #7 for count in range(total): number = int(input('Enter a positive integer: ')) while number < 1 or number > 100: #6b range check number = int(input('Out of range, please re-enter a positive integer: ')) if number >= 1 and number <= 40: print(number, '- Low') elif number > 40 and number <= 70: print(number, '- Medium') elif number > 70 and number <= 100: print(number, '- High') highlist.append(number) #6c allnumbers = allnumbers + number #7 print("The numbers classified as high are: ", highlist) #6c print("The average of all numbers are: ", allnumbers/count) #7 3

4 Task 3 Quest ion Answer Ma rks 11 Errors are underlined word = input("Please enter your word: ") word = word.islower() begin_p = word.beginswith("p") end_h = word.endswith("h") contain_e = word("e") word_length = word.length() if not begin_p and not end_h and contain_e = -1: if word_length < 3: print("The length of the word is short.") elif word <= 10: print("The length of the word is medium.") elif: print("The length of the word is long.") if begin_p: print("You entered a word that begins with 'p'.") elif end_h: print("You entered a word that ends with 'h'.") elif not contain_e: print("You entered a word that contains 'a'.") Corrected Lines 1 word = word.lower() 1 2 begin_p = word.startswith("p") 1 3 contain_e = "e" in word 1 4 word_length = len(word) 1 5 if not begin_p and not end_h and not contain_e: 1 6 if word_length <= 3: 1 7 elif word_length <= 10: 1 8 else: 1 9 elif contain_e: 1 10 print("You entered a word that contains 'e'.") 1

5 Task 4 Questi on Answer Marks 12 Create a conversion table from ‘0’ to ‘F’ 1 Use of a loop 2 Correct calculation using % and // Return hexadecimal number 1 Questi on Answer Marks 13 Create a signature line with correct function name and parameters def randomnumber(start,end): 1 Correct use of randint with start and end values 1 Questi on Answer Marks 14 Create a signature line with correct function name and parameters def createIPv4(): Return statement 1 Call function randomnumber 4 times Concatenation of 4 numbers with ‘.’ 1 Questi on Answer Marks 15 Create a signature line with correct function name and parameters def storeIPv4(n): Return statement 1 Call function createIPv4 n times by loop 1 Store all IPv4 addresses into a list 1 Questi on Answer Marks 16 Create a signature line with correct function name and parameters def createIPv6(): Return statement 1 Use of loop / multiple statements to generate 8 segments 1 Call functions denary_to_hex and randomnumber 1 Questi on Answer Marks 17 Use of loop / multiple statements to generate 6 segments 1 Call functions denary_to_hex and randomnumber 1 Questi on Answer Marks 18 Print 3 options on 3 lines. 1 Validate input option as 1 or 2 or 3. Prompt for re-input if not 1 or 2 or 3. 1 Correct conditional statements 1 Calls all 3 functions 1

6 Sample Code: #TASK 4 HEXADECIMAL.PY #9 – 4M def denary_to_hex(number): conversion_table = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A' , 'B', 'C', 'D', 'E', 'F'] hexadecimal = '' while number>0: remainder = number%16 hexadecimal = conversion_table[remainder]+ hexadecimal number = number//16 return hexadecimal #TASK 4 RANDOM.PY #10 – 2M def randomnumber(start, end): return random.randint(start, end) #TASK 4 IPV4.PY #11 – 2M def createIPv4(): ipv4 = str(randomnumber(0,255)) + "." + str(randomnumber(0,255)) + "." + str(randomnumber(0,255)) + "." + str(randomnumber(0,255)) return ipv4 #TASK 4 STORE.PY #12 – 3M def storeIPv4(n): ipaddr = [] for x in range(n): ipaddr.append(createIPv4()) return ipaddr #TASK 4 IPV6.PY #13 – 3M def createIPv6(): #IPv6 has 8 segments of 2 bytes segments = [] for x in range(8): segments.append(denary_to_hex(randomnumber(0,65535))) #generate 8 segments IPv6 = str(segments[0]) + ":" + str(segments[1]) + ":" + str(segments[2]) + ":" + \ str(segments[3]) + ":" + str(segments[4]) + ":" + str(segments[5]) + ":" + \ str(segments[6]) + ":" + str(segments[7]) return IPv6 #TASK 4 MAC.PY #13 – 2M

7 def createMAC(): #MAC has 6 segments of 1 byte segments = [] for x in range(6): segments.append(denary_to_hex(randomnumber(0,255))) #generate 8 segments mac = str(segments[0]) + ":" + str(segments[1]) + ":" + str(segments[2]) + ":" + \ str(segments[3]) + ":" + str(segments[4]) + ":" + str(segments[5]) return mac #TASK 4 NETWORK.PY #14 – 4M print("Option 1: Create an IPv4 address") print("Option 2: Create an IPv6 address") print("Option 3: Create a MAC address") option = int(input("Please select options 1/2/3: ")) while option not in [1,2,3]: option = int(input("Re-enter options 1/2/3: ")) if option == 1: print(createIPv4()) elif option == 2: print(createIPv6()) else: print(createMAC()) -End of Paper-