Question bank

254 questions so far. 162 are checked for you: your code is run against tests, or your trace table is compared with one made by running the code (22 of the trace tables also ask one written question you mark yourself). 92 are written answers you mark yourself against the marking points.219 questions in Java so far. 18 are checked for you: your trace table is compared with one made by running the code (9 of the trace tables also ask one written question you mark yourself). 109 are code questions: Java answers can't run here yet, so they are not checked for you. 92 are written answers you mark yourself against the marking points.

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254 of 254 questions

Name the main components of a CPU and state what each one does

P1 a1 cpu registersShort answer●●●●●

Explain what cache memory is for and what a cache hit and a cache miss mean

P1 a1 cache memoryShort answer●●●●●

Describe the fetch, decode and execute cycle step by step

P1 a1 fetch decode executeShort answer●●●●●

Explain pipelining and how overlapping instruction stages raises throughput

P1 a1 pipeliningShort answer●●●●●

Compare internal and external secondary storage types including HDD, SSD, optical, flash and network attached storage

P1 a1 storage choiceShort answer●●●●●

Convert between denary, binary and hexadecimal

P1 a1 binary hexShort answer●●●●●

Explain how integers are stored, including a representation for negative numbers

P1 a1 twos complementShort answer●●●●●

Explain how a bitmap image is stored, and how resolution and colour depth affect file size

P1 a1 bitmap sizeShort answer●●●●●

Write the Boolean expression for a described condition

P1 a1 greenhouse logicShort answer●●●●●

Explain how the operating system allocates and protects memory between processes

P1 a1 memory protectionShort answer●●●●●

Compare scheduling approaches such as round robin, priority and first come first served

P1 a1 round robinShort answer●●●●●

Compare polling and interrupts as ways for hardware to get the processor's attention

P1 a1 interruptsShort answer●●●●●

Compare interpreters and compilers on error detection, translation time, execution speed and portability

P1 a1 compiler or interpreterShort answer●●●●●

Explain what bytecode is and how a virtual machine executes it

P1 a1 bytecode jitShort answer●●●●●

State the function of a router, switch, modem, gateway, network interface card, wireless access point and firewall

P1 a2 school devicesShort answer●●●●●

Compare TCP and UDP and say when each is the right transport protocol

P1 a2 tcp or udpShort answer●●●●●

Name the four layers of the TCP/IP model and state what each is responsible for

P1 a2 tcpip layersShort answer●●●●●

Trace a piece of data down and back up the TCP/IP layers, describing encapsulation

P1 a2 encapsulationShort answer●●●●●

Describe common network topologies including star, mesh and hybrid

P1 a2 star or meshShort answer●●●●●

Describe how a DNS lookup resolves a domain name to an IP address

P1 a2 dns lookupShort answer●●●●●

Interpret CIDR notation to identify a network range

P1 a2 cidr subnetShort answer●●●●●

Explain what an IP address is and how it differs from a MAC address

P1 a2 ip mac natShort answer●●●●●

Explain packet switching and what a packet contains

P1 a2 packet switchingShort answer●●●●●

Explain what a firewall does and where it sits in a network

P1 a2 firewall limitsShort answer●●●●●

Describe common network attacks including DoS and DDoS, man in the middle, phishing, malware, SQL injection and cross-site scripting

P1 a2 phishing layersShort answer●●●●●

Explain what encryption does and distinguish plaintext from ciphertext

P1 a2 symmetric asymmetricShort answer●●●●●

Explain what a primary key is and why every table needs one

P1 a3 library keysShort answer●●●●●
P1 case trip keysShort answer●●●●●

Identify one-to-one, one-to-many and many-to-many relationships in a scenario

P1 a3 bike share relationshipsShort answer●●●●●

Describe the data anomalies that poor design causes on insert, update and delete

P1 a3 drama club anomaliesShort answer●●●●●

Read an entity relationship diagram and state the entities, attributes and relationships it describes

P1 a3 music school designShort answer●●●●●

Choose appropriate SQL data types such as INTEGER, REAL, BOOLEAN, CHAR, VARCHAR and DATE for given attributes

P1 a3 weather data typesShort answer●●●●●

Identify partial and transitive dependencies in a table

P1 a3 cafe normaliseShort answer●●●●●

Write a single-table SELECT query using WHERE, ORDER BY and DISTINCT

P1 a3 library select joinShort answer●●●●●

Write INSERT, UPDATE and DELETE statements, and explain the consequence of omitting a WHERE clause

P1 a3 library updateShort answer●●●●●

Use the aggregate functions COUNT, SUM, AVG, MIN and MAX in a query

P1 a3 canteen group byShort answer●●●●●

Explain what a transaction is and why some operations must succeed or fail as a unit

P1 a3 wallet transactionShort answer●●●●●

Compare relational and non-relational approaches on schema flexibility, scaling and consistency

P1 a3 fitness document dbShort answer●●●●●

Explain what machine learning is and how it differs from a conventionally programmed solution

P1 a4 ml or rulesShort answer●●●●●

Distinguish supervised, unsupervised and reinforcement learning

P1 a4 learning typesShort answer●●●●●

Distinguish classification from regression as supervised tasks

P1 a4 weather predictShort answer●●●●●
P1 case demand modelShort answer●●●●●

Compare running a model on an edge device with running it in a data centre or cloud platform

P1 a4 camera edgeShort answer●●●●●

Recommend a hardware deployment for a described machine learning scenario and justify it

P1 case five minute updatesShort answer●●●●●

Explain why raw data must be cleaned before training and what happens if it is not

P1 case trip cleaningShort answer●●●●●

Identify data quality problems such as missing values, duplicates, outliers and inconsistent formats

P1 a4 clean readingsShort answer●●●●●

Explain what feature selection is and why fewer, better features can improve a model

P1 a4 feature choiceShort answer●●●●●

Interpret a fitted regression line and use it to make a prediction

P1 a4 regression lineShort answer●●●●●

Evaluate a classifier using accuracy and the counts of correct and incorrect predictions per class

P1 a4 phishing accuracyShort answer●●●●●

Explain what a hyperparameter is and how it differs from a learned parameter

P1 a4 tree depthShort answer●●●●●

Explain why a model must be evaluated on data it was not trained on

P1 case test splitShort answer●●●●●

Explain how bias enters a machine learning system through data, labels or design choices

P1 a4 support biasShort answer●●●●●
P1 case outer fairnessShort answer●●●●●

Apply decomposition to break a problem into sub-problems

P2 b134 cinema decomposeShort answer●●●●●

Design an algorithm as an ordered sequence of unambiguous steps

Seats togetherCoding exercise●●●●●

Question bank

Name the main components of a CPU and state what each one does

Explain what cache memory is for and what a cache hit and a cache miss mean

Describe the fetch, decode and execute cycle step by step

Explain pipelining and how overlapping instruction stages raises throughput

Compare internal and external secondary storage types including HDD, SSD, optical, flash and network attached storage

Convert between denary, binary and hexadecimal

Explain how integers are stored, including a representation for negative numbers

Explain how a bitmap image is stored, and how resolution and colour depth affect file size

Write the Boolean expression for a described condition

Explain how the operating system allocates and protects memory between processes

Compare scheduling approaches such as round robin, priority and first come first served

Compare polling and interrupts as ways for hardware to get the processor's attention

Compare interpreters and compilers on error detection, translation time, execution speed and portability

Explain what bytecode is and how a virtual machine executes it

State the function of a router, switch, modem, gateway, network interface card, wireless access point and firewall

Compare TCP and UDP and say when each is the right transport protocol

Name the four layers of the TCP/IP model and state what each is responsible for

Trace a piece of data down and back up the TCP/IP layers, describing encapsulation

Describe common network topologies including star, mesh and hybrid

Describe how a DNS lookup resolves a domain name to an IP address

Interpret CIDR notation to identify a network range

Explain what an IP address is and how it differs from a MAC address

Explain packet switching and what a packet contains

Explain what a firewall does and where it sits in a network

Describe common network attacks including DoS and DDoS, man in the middle, phishing, malware, SQL injection and cross-site scripting

Explain what encryption does and distinguish plaintext from ciphertext

Explain what a primary key is and why every table needs one

Identify one-to-one, one-to-many and many-to-many relationships in a scenario

Describe the data anomalies that poor design causes on insert, update and delete

Read an entity relationship diagram and state the entities, attributes and relationships it describes

Choose appropriate SQL data types such as INTEGER, REAL, BOOLEAN, CHAR, VARCHAR and DATE for given attributes

Identify partial and transitive dependencies in a table

Write a single-table SELECT query using WHERE, ORDER BY and DISTINCT

Write INSERT, UPDATE and DELETE statements, and explain the consequence of omitting a WHERE clause

Use the aggregate functions COUNT, SUM, AVG, MIN and MAX in a query

Explain what a transaction is and why some operations must succeed or fail as a unit

Compare relational and non-relational approaches on schema flexibility, scaling and consistency

Explain what machine learning is and how it differs from a conventionally programmed solution

Distinguish supervised, unsupervised and reinforcement learning

Distinguish classification from regression as supervised tasks

Compare running a model on an edge device with running it in a data centre or cloud platform

Recommend a hardware deployment for a described machine learning scenario and justify it

Explain why raw data must be cleaned before training and what happens if it is not

Identify data quality problems such as missing values, duplicates, outliers and inconsistent formats

Explain what feature selection is and why fewer, better features can improve a model

Interpret a fitted regression line and use it to make a prediction

Evaluate a classifier using accuracy and the counts of correct and incorrect predictions per class

Explain what a hyperparameter is and how it differs from a learned parameter

Explain why a model must be evaluated on data it was not trained on

Explain how bias enters a machine learning system through data, labels or design choices

Apply decomposition to break a problem into sub-problems

Design an algorithm as an ordered sequence of unambiguous steps

Read a flowchart and state what the algorithm it describes does

Trace a flowchart with given inputs and produce the correct output, using a trace table

Declare and assign variables of the common primitive types

Choose an appropriate data type for a given value and explain why

Distinguish local from global scope and predict which value a name refers to

Trace a program by hand and record variable values at each step in a trace table

Apply arithmetic, comparison and logical operators correctly, including operator precedence

Convert between data types explicitly and explain when conversion loses information

Extract a substring from a string by position

Manipulate strings by concatenating, searching, replacing and changing case

Split a string on a delimiter and rejoin parts

Explain what an exception is and when a program should handle one

Write code that catches an exception and recovers, rather than crashing

Validate input so that bad data is rejected before it causes an error

Distinguish syntax, runtime and logic errors and identify which one a described failure is

Debug a program using tracing, test output and breakpoints, and explain the fix

Design test cases including normal, boundary and invalid inputs

Distinguish static from dynamic data structures

Compare static and dynamic structures on memory use, flexibility and access speed

Create, index, update and iterate over a one-dimensional array or list

Write code that searches or accumulates over a list

Create and traverse a two-dimensional array or list, including by row and by column

Trace code that manipulates an array or list and state the final contents

Explain the last in, first out behaviour of a stack and name its operations

Trace a sequence of push and pop operations and state the stack contents at the end

Identify a problem that a stack solves naturally and explain why

Explain the first in, first out behaviour of a queue and name its operations