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QUESTION 3 This data dictionary is for a table containing data on basketball players in a professional league. Table: players Column name Data type playernumber VARCHAR es playerheight INTEGER Primary key? Length playername TEXT teamname VARCHAR Yes The following SQL query returned an error on execution: INSERT INTO players (teamname playernumber VALUES ('Raptors' '2' ‘Edward Lee' 183.5); Which column needs to be adjusted for the query to work? (A) playernumber (B) playerheight (C) playername (D) teamname playername < I) 10 playerheight)
QUESTION 9 The table describes a sample of the personalised numberplate range for Queensland. Range Classic Emoji 3 alphabetic characters and 1 emoji Combination of 3 numeric characters and Combination of 5 alphanumeric characters Which SQL statement is correct for ordering a new personalised numberplate? (A) CREATE TABLE orders product range = ‘classic theme’ combination = ‘YIP333’ customerId = 123; (B) INSERT INTO orders (customerId product range combination) VALUES (123 ‘classic theme’ ‘YIP333’) (C) UPDATE orders SET product range = ‘classic theme’ combination = ‘YIP333’ WHERE customerlId = 123; (D) ALTER TABLE orders SET product range = ‘classic theme’ combination WHERE customerld = 123; *YIP333’
QUESTION 9 This table contains the posts published to a rock climbing group on a social networking site. Table: posts 15/06/2019 Would anyone like to rock climb tomorrow? ae 15/06/2019 Lui Chan Who is going to the boulder festival? 14/06/2019 Lui Chan Who wants to go to yoga tonight? 14/06/2019 Amy Smith Has anyone picked up a chalk bag? > An SQL query is executed: SELECT Date Author SUM(Likes) FROM Posts GROUP BY Date Author What is the output of this query? SUMiTibe 15/06/2019 Lui Chan Would anyone like to rock climb tomorrow? 20 | 14/06/2019 Lui Chan Who wants to go to yoga tonight? To 14/06/2019 Amy Smith Has anyone picked up a chalk bag? 9 | (B) Author SUM(Likes) 15/06/2019 | Lui Chan 27 14/06/2019 Amy Smith 9 14/06/2019 Lui Chan ‘seer | o) SUMITiRES (C) SUM(Likes) 14/06/2019 Amy Smith 9 |
QUESTION 6 Desk check the algorithm to predict the output for numX = 8 and numZ = 5. BEGIN SET numX user input SET numZ user input IF numxX < 10 AND numZ > 10 THEN OUTPUT “Condition 1” ELSE numX > 5 OR numZ < 5 THEN OUTPUT “Condition 2” ELSE numX > 5 OR numZ < 10 THEN OUTPUT “Condition 3” ELSE OUTPUT “Condition 4” ENDIF END (A) Condition 1 (B) Condition 2 (C) Condition 3 (D) Condition 4
QUESTION 1 Converting a variable-length set of data to a fixed-length hexadecimal value is known as (A) hashing. (B) checksum. (C) encryption. (D) authentication.
QUESTION 6 This algorithm determines the total points a player receives from rolling a standard six-sided dice three times. BEGIN SET points = 0 SET count = 0 REPEAT SET result = random number between 1 and 6 inclusive (roll die) SET number on die as result IF result = 1 THEN points = points + 100 ELSE IF result = 5 points = points + 50 ENDIF ENDIF INCREMENT count UNTIL count = 3 END How many points will a player receive if they roll a 2 then a 3 followed by a 5? (A) 50 (B) 100 (C) 150 (D) 200
QUESTION 10 In a game scores are averaged for players in the same team. Each team consists of five players. Player names and scores are to be stored in arrays. The referee was given the first version of the algorithm which they then improved to create the second version. First version Second version ProcessGroup (name[] score[]) ProcessGroup (name[] score[]) BEGIN BEGIN SET total = 0 SET groupSize = 5 PRINT name[1] SET count = 0 CALCULATE total SET total = 0 PRINT name[2] WHILE count < groupSize CALCULATE total PRINT name[count] PRINT name[3] CALCULATE total = total + score[count] CALCULATE total INCREMENT count PRINT name[4] ENDWHILE CALCULATE total CALCULATE average = total / groupSize PRINT name[5] PRINT average CALCULATE total total + END CALCULATE average = total PRINT average END Which features of good algorithms have been improved in the second version? (A) efficiency effectiveness (B) reliability effectiveness (C) maintainability efficiency (D)_ reliability maintainability
QUESTION 10 Desk check the algorithm to determine its output. BEGIN 6 SET Y = 12 SET X WHILE (X < Y) INCREMENT X Y = PROCESS1(X Y) ENDWHILE OUTPUT Y END BEGIN PROCESS1 (A B) CALCULATE C = (B — A) x 2 RETURN C END PROCESS1 The output value is (A) -10 (B) 4 (C) 8 (D) 10
QUESTION 9 Which algorithmic statement determines the value of y between 10 and 50 inclusive? (A) IF 10 > y OR y > 50 (B) IF 10 > y AND y < 50 (C) IF y >= 10 OR y <= 50 (D) IF y >= 10 AND y <= 50
QUESTION 13 (12 marks) A games arcade has developed a digital solution for recording members’ points. Members receive a membership card which they scan when they play games at the arcade. The card records how many points a member receives from winning a game. A sample of the data is shown. memes CS members_activity Ee a) Develop an algorithm to list all members by name. Sort the list alphabetically by last name. [4 marks] b) Develop an algorithm to list member IDs and join dates for memberships of 10 or more years. Sort the list by join date in ascending order. [4 marks] c) Develop an algorithm to provide the contact details for members who currently have more than 3000 points. [4 marks]
QUESTION 12 (8 marks) Marine markers are placed throughout Queensland waterways. Each marine marker is fitted with an Internet of Things (IoT) device that can broadcast a fault status via a satellite internet link. Each day the IoT device checks the status of the marker. If a fault is detected the device broadcasts the marker’s unique identifier a positive fault status flag and the fault occurrence date and time. This is an example data structure provided by a marine marker’s IoI device: { OldMarineMarkerId : 3446 OldMarineMarkerFault : True OldMarineMarkerDateTime : 2020-02-02T18:00:00.0002 } A request has been made for a quarterly release of an ongoing summary of fault issues per area. The information will be centrally stored in this way: MarineMarkerStatus [MarkerID MarkerType AreaDescription Latitude Longitude Fault Detected] gD eee Ne ) vy ZFS —1G \ SW (Ss TS= a) Evaluate the proposed solution against the criteria of reliability and accuracy. [2 marks] Reliability: Accuracy: b) State two additional criteria and evaluate the proposed solution against these criteria. [4 marks] Criterion: Criterion: c) Justify why JSON is an effective method of data exchange between the marine markers and the central database system. Provide two reasons to justify your response. [2 marks]
QUESTION 13 (12 marks) Refer to Stimulus 2 in the stimulus book. a) b) Use pseudocode to symbolise a one-time pad encryption algorithm with any lower case letters. Users must input the plain text and key. [7 marks] Evaluate the encryption algorithm developed in Question 13a) by performing a desk check. Use the plain text and key provided. Specify all inputs and outputs in table form. Plain text: Queens Key: ryjwah Example output: hsnanz [5 marks]
QUESTION 15 (17 marks) Refer to Stimulus 2 in the stimulus book. Stimulus 2 is an extract from a university course database that shows enrolled students assessment items and student results for each assessment item. The following query was developed to show all students (by ID) and their overall subject result. SELECT ID SUM (Mark / 100) FROM Results Assess GROUP BY Item a) Evaluate the query and identify and describe any errors. [6 marks] b) Refine the query to ensure it functions correctly. Justify the refinements made. [7 marks] c) Refine the query in 15b) to show only students with a subject rank of ‘A’. [4 marks]
QUESTION 16 (24 marks) In security systems it is common practice to use a unique identifier of a numeric type for example a door lock code or PIN. People often store these numbers in an unsecured text file on personal devices. A simple encryption method for a two-digit number is shown below. é $ % A & * ( ) 3 4 5 6 7 718 8}19 of} 0 Plaintext Block key Encrypted Ciphertext number number character '4Q! 1 7 3 9 55 8 2 0 4 6 5 % 5! 12 3 4 5 6 7 8 9 0 6 “ Therefore the Plaintext number '45 ' would output Ciphertext '%*'. a) Develop a low-fidelity prototype solution key for any four-digit PIN (e.g. 7826) with associated key and predicted output. The algorithm must read data from a user input and output encrypted data to a file. Annotate the pseudocode in the table below to identify the location of assignment condition and modularisation. Evaluate the algorithm using a desk check and write the output at each step. [18 marks] Original Key Encrypted number Character b) Compare this encryption method with a standard Caesar cipher explaining three advantages and/or disadvantages of each method. Explain which of these two methods is the more secure method to use and justify your response. [6 marks]
QUESTION 12 (8 marks) Refer to Stimulus | in the stimulus book. a) Describe the listed algorithm constructs and identify one example of each from the stimulus. Use corresponding line numbers to identify examples. [6 marks] Assignment: Example: Condition: Example: Iteration: Example: b) Explain the purpose of modularisation and identify an example of how it is used in the stimulus. Use corresponding line numbers in your response. [2 marks]
QUESTION 9 The following extract from a medical database shows patients vaccines by item number date vaccination is due date immunised and the risk of contracting the disease post-immunisation. Patients ID First 1684 John 2893 Mary 3642 Jackie 1206 Michael 1910 Midori 1934 Beatrice 1935 Wanda Assess Item Vaccine 1 Measles 2 Polio 3 Tetanus SELECT first FROM results r INNER JOIN assess a ON r.item = INNER JOIN patients p ON p.id = WHERE a.item in AND r.immunised < a.due ; Last Jones Smith Joyce Mentos Ono Thompson Granger Risk 0.001 0.00021 0.0005 last (1 2) The query above determines (A) (B) (C) (D) Due 1990-09-08 1990-10-21 1990-12-02 immunised Results Item \ DO Ww W W WwW W NY NHN NY KN WN a.item r.id ID 1684 2893 1206 1934 1935 3642 1684 3642 1934 2893 1935 3642 1934 2893 1935 1684 1206 Immunised 1990-09-08 1990-09-07 1990-09-08 1990-09-10 1990-09-06 1990-09-09 1990-10-21 1990-10-22 1990-10-21 1990-10-22 1990-10-21 1990-12-10 1990-12-08 1990-11-30 1990-11-30 1990-12-07 1990-12-11 Risk -001 .00021 .0005 .001 .0005 .00021 .0005 001 .0005 .0006 .00021 .0007 .O01 .0014 .00021 O01 004 o.UlUCOOlmlCO CO COT CT i TT i TT Tt Tt Tt TT Tt Tt lc Tt lO the first name last name and immunisation date for all patients who received items before they were due. the first name last name and immunisation date for patients who received Items | and 2 after they were due. the first name last name and immunisation date for patients who received Item | or Item 2 before it was due. the first name last name and immunisation date for patients who received Items 1 and 2 before they were due.
QUESTION 4 The table below shows two algorithms. Program 1 Program 2 BEGIN Main numl = 50 Sub () PRINT numl END Main BEGIN Sub numl is local numl = 20 END Sub BEGIN Main numl is global numl = 50 Sub () PRINT numl END Main BEGIN Sub numl = 20 END Sub Select the correct output when both programs are run. Program 1 Program 2 (A) 50 20 (B) 50 50 (C) 20 50 (D) 20 20
QUESTION 10 The table shown is named 'Planets' and is stored in a database. Name Moons Diameter Gravity Mean ar eC Which SQL query will return the name and mean temperature of any planet with a diameter less than 50 000 ordered in descending order of mean temperature? (A) (B) (C) (D) SELECT Name MeanTemperature FROM Planets WHERE Diameter < 50000 AND ORDER BY MeanTemperature DESC SELECT Name MeanTemperature FROM Planets WHERE Diameter < 50000 ORDER BY MeanTemperature DESCENDING SELECT Name MeanTemperature FROM Planets WHERE Diameter < 50000 ORDER BY MeanTemperature DESC SELECT Name MeanTemperature FROM Planets WHERE Diameter < 50000 AND ORDER BY MeanTemperature DESC
QUESTION 7 The algorithm outputs a data set according to values a user inputs. BEGIN INPUT firstNum INPUT secondNum FOR j = 1 TO secondNum CALCULATE result = 1 * 5 1 2 3 4 FOR i = 1 TO firstNum 5 6 7 OUTPUT i * 93 = result 8 ENDFOR 9 ENDFOR 10 END If the user inputs firstNum = 6 and secondNum = 10 how many times would line 6 be executed? (A) 1 (B) 6 (C) 10 (D) 60
QUESTION 8 An open data set contains plain text of the facilities available in Queensland parks. To develop a mobile application that identifies basketball courts in a suburb it is necessary for data to be (A) retrieved normalised and verified. (B) retrieved normalised and validated. (C) normalised validated and encrypted. (D) retrieved modularised and validated.
QUESTION 5 Which encryption method uses a fixed shift of letters down the alphabet with a modulus operation? (A) Caesar (B) Vigenere (C) Gronsfeld (D) One-time pad
QUESTION 13 (9 marks) A one-time pad algorithm encrypts an 8-character word and outputs the result. The algorithm uses 0 as the first index in an array. There are four errors on lines 9 to 21 inclusive. 1 BEGIN 2 INPUT word 3 word = word converted to lowercase _ plainText = word converted to an array 5 //The GenerateOTPKey function will return an array of 8 random numbers 6 key = GenerateOTPKey () 7 cipherText = array of 8 blank characters 8 alphabet = lowercase alphabet converted to an array 9 FOR i =0 to 9 10 alphabetLocation = -1 11 FOR 3 =0 to 25 12 IF plainText[j] = alphabet [i] 13 alphabetLocation =] 14 ENDIF 15 ENDFOR 16 /Check if not found 17 IF alphabetLocation 2 0 THEN 18 cipherText[i] = alphabet (alphabetLocation + key[i])mod 26 19 ENDIF 20 ENDFOR 21 OUTPUT cipherText[i] 22 END Use pseudocode to correct the four errors on lines 9 to 21. Justify your response.
QUESTION 3 The following algorithm is used to produce an output based on different input data values. BEGIN IF valuel > value2 PRINT A ELSE IF value3 S$ (valuel + value2) PRINT B ELSE PRINT C ENDIF ENDIF IF (value3 - valuel) 2 value2 PRINT D ENDIF END Identify the output produced by the algorithm when valuel = 7 value2 = 8 and value3 = 15. (A) AD (B) BC (C) CD (D) BD
QUESTION 8 An algorithm is developed to establish a seating plan in a movie theatre so that individual bookings are always separated by two seats. To maximise ticket sales bookings of four or more guests are accepted immediately. Bookings for smaller groups are not confirmed until 2 hours before the movie starts. BEGIN SET seats = true //assume seats are available SET bookingConfirmed = false SET DateTime //current date and time INPUT movieStartTime INPUT guestNumber IF guestNumber < 4 AND IF movieStartTime —- DateTime >= 2 hours SET bookingPending = true ELSE IF guestNumber >= 4 THEN SET bookingConfirmed = true ENDIF ENDIF ENDIF BEGIN bookingPending //module to handle bookings for fewer than 4 guests END BEGIN bookingConfirmed //module to handle bookings for 4 or more guests END END The algorithm is incomplete. What is the best way to make the algorithm more efficient? (A) Use modularisation to suggest an alternative movieStartTime for bookingPending. (B) Add an algorithm to determine seat allocation ensuring groups sit two seats apart. (C) CalculatemovieStartTime - DateTime and set as a Boolean. (D) Use a FOR loop to check the parameters for bookingConfirmed.
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