Advanced level 2026 Holy Infant High School mock Computer science guide
Advanced level 2026 Holy Infant High School mock Computer science guide
I have extracted the text from your final image, which contains the Answer Key and Explanations for the previously uploaded Computer Science questions.
COMPUTER SCIENCE ANSWER KEY & EXPLANATIONS
1. C ($ABC’ + AB’C + A’BC$). The question requires the output to be 1 only when exactly two inputs are 1. Each term in option C represents exactly two 1s: $(A=1, B=1, C=0)$, $(A=1, B=0, C=1)$, or $(A=0, B=1, C=1)$.
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A: NOR gate.
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B: AND gate.
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D: OR gate.
2. A (X, Z). Operations:
Push(X) $\rightarrow$ [X]; Push(Y) $\rightarrow$ [X, Y]; Pop() $\rightarrow$ [X]; Push(Z) $\rightarrow$ [X, Z]; Push(W) $\rightarrow$ [X, Z, W]; Pop() $\rightarrow$ [X, Z].
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B: This reverses the order; stacks are LIFO (Last-In, First-Out).
3. C ((i) and (iv) only). The ER diagram shows a 1-to-M relationship between Lecturer and Course. In a 1-to-M relationship, the primary key of the “1” side (NIC) becomes a foreign key in the “M” side (Course).
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A/D: Contains redundant data. B: Only necessary for M-to-M relationships.
4. D (Patents). Patents protect new inventions, devices, or processes, granting the inventor exclusive rights for a limited period.
5. D (Switch). A switch is the standard device used within a LAN to forward data packets specifically to the destination MAC address.
6. B (Device A: Switch, Device B: Server, Device C: Router). Looking at the diagram, Device A connects the local PCs (Switch), Device B connects the printer/resources (often a Server), and Device C connects the whole network to the Internet (Router).
7. D (Requirements cannot be easily changed…). The Waterfall model is linear and rigid; once a phase begins, going back to change requirements is very difficult and costly.
8. C (P4). At time 2, P2 has 3ms left ($5 – 2$). P4 arrives with a burst of 2ms. Since SRTF (Shortest Remaining Time First) always picks the shortest remaining time, P4 (2ms) is shorter than P2 (3ms), so P4 runs at time 3.
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Timeline: $[0-2: P2] \rightarrow [2-4: P4] \rightarrow [4-7: P2] \rightarrow [7-15: P3] \rightarrow [15-25: P1]$
9. B (The variable val is updated to 20). *ptr is the dereference operator. By assigning *ptr = 20, you are changing the value stored at the address ptr points to, which is the variable val.
10. B (Provide reports… to support structured decision-making). The primary goal of an MIS is to process data into meaningful reports that help managers make informed, structured decisions.
11. B (To ensure unique representation and maximize precision). Normalization ensures that there is only one way to represent a specific number (by having a non-zero digit after the binary point) and uses the available bits for the mantissa most efficiently.
12. D (*). In the expression $((A + B) * (C / D))$, the multiplication is the last operation performed because it joins the two parenthesized sub-expressions. Therefore, it is the root of the tree.
13. C (storing data online). Storing data online (cloud storage) depends on internet connectivity and the service provider, not the local RAM or HDD/SSD specs.
14. A (It focuses on the internal logic…). White-box testing requires knowledge of the code’s internal structure and paths, whereas black-box testing only focuses on inputs and outputs.
15. C (Compiler). A compiler translates the entire source code into machine code as a single batch before execution.
16. B (A blueprint or template for creating objects). In OOP, a class defines the properties (attributes) and behaviors (methods) that the objects created from it will have.
17. A (When the loop body should potentially never execute…). A ‘While’ loop tests the condition before entering the loop, so if the condition is false initially, the body never runs. A ‘Repeat-Until’ loop tests at the end, so it always runs at least once.
18. C (7). Table size 10, $h(k) = k \pmod{10}$:
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Key 25: $25 \pmod{10} = 5$. Index 5 is filled.
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Key 35: $35 \pmod{10} = 5$. Index 5 is full; linear probing moves to index 6. (Note: If index 6 were also full, it would move to 7).
Would you like me to create a summary of these topics (like CPU Scheduling or Normalization) to help your students review for the GCE?
