0478_s23_qp_21

1 (a) Four descriptions of stages in the program development life cycle are shown.

Draw one line to link each description to its most appropriate program development life cycle stage.

Not all program development life cycle stages will be used. Program development life cycle description Program development life cycle stage develop an algorithm to solve the problem by using structure diagrams, flowcharts or pseudocode analysis coding design evaluation testing detect and fix the errors in the program identify the problem and its requirements write and implement the instructions to solve the problem

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(b) Identify three of the component parts after a problem has been decomposed. 1 2 3 [3]

4 Explain the purpose of the library routines DIV and ROUND DIV ROUND [4]

2 Tick (ü) one box to show the name of the data structure used to store a collection of data of the same data type.

A Array

B Constant

C Function

D Variable

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3 (a) Describe what is meant by data validation [2]

(b) A validation check is used to make sure that any value that is input is an integer between 30 and 200 inclusive.

Give one example of each type of test data to check that the validation check is working as intended. Each example of test data must be different.

Give a reason for each of your choices of test data. Normal test data Reason Abnormal test data Reason Extreme test data Reason [6]

6 State two features that should be included to create a maintainable program.

Give a reason why each feature should be used. 1 2 [4]

5 An algorithm has been written in pseudocode to allow some numbers to be input. All the positive numbers that are input are totalled and this total is output at the end.

An input of 0 stops the algorithm.

01 Exit ← 1

02 WHILE Exit <> 0 DO

03 INPUT Number

04 IF Number < 0

05 THEN

06 Total ← Total + Number

07 ELSE

08 IF Number = 0

09 THEN

10 Exit ← 1

11 ENDIF

12 ENDIF

13 ENDIF

14 OUTPUT "The total value of your numbers is ", Number

(a) Identify the four errors in the pseudocode and suggest a correction for each error. Error 1 Correction Error 2 Correction Error 3 Correction Error 4 Correction [4]

(b) Describe how you could change the corrected algorithm to record and output how many positive numbers have been included in the final total.

You do not need to rewrite the algorithm [4]

7 The flowchart represents an algorithm. START INPUT Letter INPUT Choice OUTPUT "Another Letter? (Y or N)" OUTPUT "Letter ", Letter, " is represented by ", Word[Pointer, 2] IS Choice = 'Y' ? IS Word[Pointer, 1] = Letter ? STOP Pointer 1 Pointer Pointer + 1 Yes Yes No No

The table represents the two-dimensional (2D) array Word[] which stores the first half of the phonetic alphabet used for radio transmission. For example, Word[10,1] is ‘J’. Index 1 2 1 A Alpha 2 B Bravo 3 C Charlie 4 D Delta 5 E Echo 6 F Foxtrot 7 G Golf 8 H Hotel 9 I India 10 J Juliet 11 K Kilo 12 L Lima 13 M Mike

(a) Complete the trace table for the algorithm by using the input data: F, Y, D, N Pointer Letter Choice OUTPUT

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(b) Identify the type of algorithm used [1]

(c) Describe one problem that could occur with this algorithm if an invalid character was input [2]

8 The function LENGTH(Phrase) calculates the length of a string Phrase

(a) Write the pseudocode statements to: • store the string "The beginning is the most important part" in Phrase • calculate and output the length of the string • output the string in upper case [3]

(b) Write the output your pseudocode should produce [2]

9 Consider this logic expression. Z = (NOT A OR B) AND (B XOR C)

(a) Draw a logic circuit for this logic expression.

Each logic gate must have a maximum of two inputs.

Do not simplify this logic expression.

A B C Z

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(b) Complete the truth table from the given logic expression. A B C Working space Z 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1

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10 A database table called TVRange shows the main features and prices of a range of televisions. TVCode ScreenSize Satellite SmartTV SoundBar Price$ TV90SaSmSd 90 YES YES YES 9750.00 TV75SaSmSd 75 YES YES YES 8500.00 TV75SaSd 75 YES NO YES 8000.00 TV65SaSmSd 65 YES YES YES 6000.00 TV65SmSd 65 NO YES YES 5000.00 TV65SaSd 65 YES NO YES 5000.00 TV55SaSmSd 55 YES YES YES 4000.00 TV55SaSd 55 YES NO YES 3500.00 TV55SmSd 55 NO YES YES 3500.00 TV50SaSmSd 50 YES YES YES 2500.00 TV50Sa 50 YES NO NO 1750.00 TV50Sm 50 NO YES NO 1750.00 TV40Sa 40 YES NO NO 1200.00 TV40 40 NO NO NO 950.00 TV32 32 NO NO NO 650.00

(a) Give the name of the field that is most suitable to be the primary key.

State the reason for this choice. Field Reason [2]

(b) The database uses the data types: • text • character • Boolean • integer • real • date/time.

Complete the table to show the most appropriate data type for each field.

Each data type must be different. Field Data type TVCode ScreenSize SmartTV Price$

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(c) Complete the structured query language (SQL) query to return the television (TV) code, screen size and price of all Smart TVs in the database table.

SELECT TVCode, , TVRange

WHERE SmartTV = ;

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