Singapore A-Level H2 Computing central themes overview quiz (SEAB 9569) quiz

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It stores larger positive numbers than any other scheme of the same width, doubling the usable range

It removes the need for a sign bit entirely, so every bit pattern is read as a positive value

It allows subtraction to be carried out by addition, and gives a single representation of zero

It stores fractional values more precisely than a fixed-point or floating-point scheme could

$O(1)$

$O(n)$

$O(n \log n)$

$O(\log n)$

Bubble sort

Merge sort

Binary search

Hash-table lookup

Queue

Stack

Hash table

Binary search tree

It keeps all keys sorted in order so it can binary-search them in logarithmic time on every lookup

It stores only unique values and is mathematically guaranteed never to produce any collisions at all

A hash function maps a key directly to an index, so a lookup goes straight to the likely location

It scans the whole table once per lookup, comparing each stored key against the key being searched for

Execute the current instruction straight away, before any fetch or decode step takes place

Write the result of the previous instruction back to disk before starting anything else

Sort the instruction queue into priority order so the most urgent instruction runs first

Fetch the next instruction from memory using the program counter

To hold frequently used instructions and data in fast memory, reducing the time the CPU waits for slower main memory

To permanently store all of the program files and user documents so that they survive after the computer is switched off

To increase the total size of the hard disk by adding extra reserved blocks that the operating system can use

To convert binary numbers into denary so that the user can read the raw memory contents more easily on screen

To make every possible query run in constant time regardless of how the tables are joined together

To reduce data redundancy and the update anomalies it causes

To store all the data together in a single large table so that no joins are ever needed for a query

To encrypt the stored data automatically so that it cannot be read without the correct decryption key

CREATE TABLE

DROP TABLE

SELECT

ALTER TABLE

Supervised learning uses no data at all and instead works purely from rules written by the programmer

Unsupervised learning always needs a human to carefully label every single output before the model can be trained

They are simply the same technique under two different names, with no real difference in how they work

Supervised learning trains on labelled examples; unsupervised learning finds structure in unlabelled data

So packets can be routed independently and reassembled, sharing the network efficiently and recovering from loss

Because small packets travel faster than light along the cable, whereas one large block would be much slower

Because every packet from a message must take exactly the same fixed route to guarantee correct reassembly

To make the data completely impossible for anyone other than the intended recipient to read while it crosses the network

Because tracing is always faster to write than a description, so it leaves more time for the rest of the paper

Because tracing demonstrates the algorithm's exact behaviour and correctness, which is what markers reward

Because written descriptions of algorithms are explicitly banned by the syllabus and earn no marks whatsoever

Because tracing lets a candidate avoid using any technical terms, which makes the answer simpler to write