Grade 11 — Questions & Memos Grade 11

• 1.1 B) cache ✓
• 1.2 C) multithreading ✓
• 1.3 B) bandwidth ✓
• 1.4 C) primary key ✓
• 1.5 B) hot swappable ✓

• 1.1 Multitasking switches rapidly between programs on one CPU (taking turns) ✓; multiprocessing uses multiple CPU cores to do work truly in parallel ✓
• 1.2 Space on the hard drive used by the OS as if it were extra RAM ✓ when physical RAM is full ✓
• 1.3 The computer spends more time swapping data between RAM and virtual memory than doing useful work, so it slows to a crawl ✓

• Embedded: very small ✓; runs on minimal hardware — a small chip with little memory, built into one device ✓
• Desktop: large ✓; needs a full PC/laptop with a multi-core CPU and several GB of RAM ✓

• 3.1 The amount of data that can be sent over a network ✓ in a specific amount of time ✓
• 3.2 A LAN covers a small area such as one building ✓; a WAN covers a large geographic area (e.g. the internet) ✓
• 3.3 A set of rules that controls how data is exchanged between devices on a network ✓

• 4.1 Advantage: work/bank/learn from anywhere, always with you ✓; disadvantage: small screen, limited battery, data costs or privacy/distraction ✓
• 4.2 Organisations can track your movements / stalking risk / targeted ads without consent ✓

• 5.1 Any two: human error, hardware failure, power surge/outage, malware, theft, natural disaster ✓✓
• 5.2 Full = copies all files every time ✓; incremental = copies only files changed since the last backup ✓
• 5.3 Keep 3 copies, on 2 different media, with 1 off-site/in the cloud ✓

• 6.1 A field (or fields) that uniquely identifies each record in a table ✓
• 6.2 Database Management System — software used to create, manage and query a database ✓
• 6.3 Less duplication / data shared by many users / easier to keep consistent and secure ✓✓

• 7.1 A network of physical devices with sensors and internet connectivity ✓ that collect and exchange data automatically ✓
• 7.2 Volume, Velocity and Variety ✓✓

iMax := arrAge[1];
for i := 2 to N do
  if arrAge[i] > iMax then
    iMax := arrAge[i];
ShowMessage(IntToStr(iMax));

• Initialise iMax to the first element ✓
• Loop through the rest of the array ✓
• Compare and update iMax when a larger value is found ✓
• Display the result ✓

• P2.1 Reset(F) ✓
• P2.2 EOF(F) ✓
• P2.3 So the file is saved and unlocked and no data is lost ✓
• P2.4 FileExists('file.txt') (or wrap Reset in try..except) ✓

dmBooks.tblBook.Filter := 'Year > 2015';
dmBooks.tblBook.Filtered := True;

dmBooks.tblBook.Sort := 'Price ASC';

• P3.1 Filter := 'Year > 2015' ✓; Filtered := True ✓
• P3.2 Sort := 'Price ASC' ✓; ASC = ascending, cheapest first ✓

• 8.1 The layout/arrangement of devices and connections on a network ✓; e.g. star (or bus, ring, mesh) ✓
• 8.2 Guided: the signal travels along a physical cable (UTP, fibre) ✓; unguided: the signal travels through the air (Wi-Fi, Bluetooth, radio) ✓

• 9.1 Any two: much faster/higher bandwidth, immune to electrical interference, more secure (hard to tap), longer distances ✓✓
• 9.2 Cheaper / easier to install and work with ✓

• 10.1 Shaping = the ISP prioritises certain traffic over others ✓; throttling = the ISP deliberately slows the connection ✓
• 10.2 Capped = a limited amount of data per month; uncapped = no data limit ✓
• 10.3 To reduce file size → faster download/streaming and less bandwidth/storage used ✓

• 11.1 The Fourth Industrial Revolution — the fusion of digital, physical and biological technologies (AI, IoT, robotics) ✓
• 11.2 A decentralised digital ledger ✓ where data is stored in linked, tamper-resistant blocks ✓
• 11.3 Getting ideas, content, services or funding from a large group of people online ✓

• 12.1 The trail of data you leave behind online ✓
• 12.2 Active = data you intentionally share (posts, forms) ✓; passive = data collected without your knowledge (cookies, browsing history) ✓

• 13.1 Checking that entered data is reasonable and in the correct format ✓; e.g. a range check, type check, or required-field check ✓
• 13.2 Validation checks whether data is sensible/allowed ✓; verification checks whether data was entered/copied correctly (e.g. double-entry or proofreading) ✓

• P4.1 Linear search checks each element one by one ✓; binary search repeatedly halves the search range ✓
• P4.2 The array must be sorted first ✓
• P4.3 A function returns a value; a procedure performs a task but returns no value ✓

iPos := Pos(',', sLine);
sName := Copy(sLine, 1, iPos - 1);
iMark := StrToInt(Copy(sLine, iPos + 1, Length(sLine)));

• Find the comma with Pos ✓
• Copy the part before the comma into sName ✓
• Copy the part after the comma and convert to integer ✓

iCount := 0;
rTotal := 0;
dm.tblLearner.First;
while not dm.tblLearner.Eof do
begin
  if dm.tblLearner['Grade'] = 11 then
  begin
    iCount := iCount + 1;
    rTotal := rTotal + dm.tblLearner['Average'];
  end;
  dm.tblLearner.Next;
end;
if iCount > 0 then
  ShowMessage('Grade 11 learners: ' + IntToStr(iCount) +
    ', Average: ' + FloatToStrF(rTotal / iCount, ffFixed, 6, 1));

• Loop from First to Eof, advancing with Next ✓
• Only count/sum records where Grade = 11 ✓
• Divide total by count for the average, guarding against division by zero ✓

• 8.1 It connects and provides power to all the components; the central hub through which data flows ✓
• 8.2 RAM is volatile, temporary working memory; ROM is non-volatile and holds permanent start-up instructions ✓✓
• 8.3 On or very close to the CPU, so frequently used data is fetched quickly without waiting for slower RAM ✓

• 9.1 A compiler translates the whole program to machine code at once (before running); an interpreter translates and runs it one line at a time ✓✓
• 9.2 Using software to run one or more "virtual" computers on one physical machine ✓; benefit: saves cost/space/electricity, or lets you test risky software safely ✓

• 10.1 Database Management System ✓ — software used to create, manage and query a database ✓
• 10.2 A personal database is on one computer for a single user; a centralised database is stored on a server and shared by many users over a network ✓✓

• 11.1 Getting ideas, content, services or funding from a large group of people online ✓; e.g. Wikipedia, crowdfunding (BackaBuddy), map/review contributions ✓
• 11.2 The gap between people who have access to digital technology and those who do not ✓

for i := 1 to N - 1 do
  for j := i + 1 to N do
    if arrMark[j] > arrMark[i] then
    begin
      // swap BOTH arrays at the same index
      iTemp := arrMark[i]; arrMark[i] := arrMark[j]; arrMark[j] := iTemp;
      sTemp := arrName[i]; arrName[i] := arrName[j]; arrName[j] := sTemp;
    end;

• Compare marks with > for descending order ✓
• Swap arrMark at i and j using a temp ✓
• Swap arrName at the same index so the name stays with its mark ✓
• Correct nested-loop structure ✓