CAPE Computer Science Unit 1 · 2012 · Paper 2

32 questions and parts from this paper. Open one to see it in full, then practise it on Quelpr and get it marked against the mark scheme.

1. 1(a)(i)4 marksGive the truth table of the circuit.
2. 1(a)(ii)6 marksUsing only primary logic gates, design and draw the circuit for F.
3. 1(b)(i)4 marksDraw a clearly labelled block diagram of a 4-to-1 line multiplexer.
4. 1(b)(ii)6 marksExplain how a multiplexer can be used for the described purpose and discuss how data from each sensor is transmitted through the alarm notification line.
5. 1(c)(i)2 marksShowing all working, find the largest and smallest integers that can be stored in four bits when signed magnitude representation is used.
6. 1(c)(ii)3 marksConsider a floating point representation with a 1-bit sign, 3-bit exponent, and 5-bit mantissa. Calculate the decimal equivalent of 101100011.
7. 2(a)(i)2 marksExplain what is meant by the 'instruction set' of a central processing unit (CPU).
8. 2(a)(ii)6 marksBriefly describe THREE types of instructions that are typically included in an instruction set.
9. 2(a)(iii)3 marksExplain how cache memory can increase the efficiency of data retrieval.
10. 2(b)(i)2 marksDistinguish between the opcode and the operands of an instruction.
11. 2(b)(ii)6 marksTwo typical instruction formats are one-address and two-address. Describe how the operands are obtained in EACH case and specify where the results are stored.
12. 2(c)(i)3 marksExplain how a hard disk differs from RAM in terms of access method and access speed.
13. 2(c)(ii)3 marksExplain how RAM differs from a CD-R device in terms of volatility and storage capacity.
14. 3(a)2 marksExplain the role of an algorithm in the problem-solving process.
15. 3(b)(i)3 marksWhich of the algorithms illustrates bounded iteration? Justify your answer.
16. 3(b)(ii)3 marksWhich of the algorithms illustrates unbounded iteration? Justify your answer.
17. 3(c)(i)5 marksWrite an algorithm to find and print the number of students that voted for EACH of the colours: red, blue, green.
18. 3(c)(ii)5 marksWrite an algorithm to find and print the TOTAL number of students that voted for red, blue or green.
19. 3(d)7 marksWrite an algorithm that uses iteration to find the sum of all multiples of 4 and all multiples of 7 between m (inclusive) and n (inclusive) where m and n are two positive integers entered via the keyboard, assuming n >…
20. 4(a)12 marksConstruct a flow chart to represent the given algorithm calculating commission based on numDays and numItemsSold.
21. 4(b)3 marksGiven the input data line '3 2 1 5 7 4', determine what the provided algorithm would print. Show your working.
22. 4(c)10 marksTrace through the execution of the provided algorithm and draw the output exactly as generated, noting the definitions of printSpaces, print, and println.
23. 5(a)6 marksBriefly describe THREE stages of the program translation process.
24. 5(b)7 marksWrite a C function which accepts a positive integer, n, and returns 2^n. State any assumptions made.
25. 5(c)(i)7 marksWrite C code to store the even numbers from 2 (inclusive) to 40 (inclusive) in a file called "num.dat".
26. 5(c)(ii)5 marksWrite C code to read the integers from the file "num.dat" created in (c)(i), add 5 to each integer and print the result on the screen.
27. 6(a)6 marksExplain THREE ways in which good programming style can be maintained.
28. 6(b)(i)2 marksWrite a declaration for a C struct productRec that can store the record for each product.
29. 6(b)(ii)1 markDeclare TWO variables, item1 and item2, that have the record structure declared in (b)(i).
30. 6(b)(iii)2 marksWrite C code to put data in the item1 struct declared in (b)(ii) using any values.
31. 6(b)(iv)3 marksAssuming two productRec structs, item3 and item4, are already loaded with data, write C code to exchange their values.
32. 6(c)11 marksWrite C code to read a 7-character uppercase string into a character array, print each vowel present in the string (or 'NO VOWELS' if none are present), and count and print the number of occurrences of the letter 'A'.