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App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 343 · 40 questions
TalentJR

Developer's tip (Box, list, place): A variable holds one value; a list holds many in order. Positions start at 0. push adds to the end; pop takes off the last item; length is how many items. On the phone: works offline, private. In the cloud: shared, any device, needs the internet.

NameDateTime takenScore ___ / 40
  1. 1.💾 Which can hold many values in order? (a) a list (b) a button (c) a single number (d) a switch
  2. 2.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Zoya", "Riya", "Kabir"];
    show(friends[0]);     (a) Riya (b) Zoya (c) Meera (d) Kabir
  3. 3.💾 What number does this code show?
    let friends = ["Aman", "Arjun", "Riya", "Kabir"];
    friends.push("Meera");
    show(friends.length);
  4. 4.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
  5. 5.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) never need a password (c) skip the internet (d) shrink the app
  6. 6.💾 What number does this code show?
    let lives = 3;
    lives = lives - 2;
    lives = lives + 3;
    show(lives);
  7. 7.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Riya", "Aman", "Arjun", "Meera"];
    show(friends[0]);     (a) Kabir (b) Arjun (c) Riya (d) Aman
  8. 8.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
  9. 9.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 5;
    show(lives);
  10. 10.💾 What number does this code show?
    let friends = ["Aman", "Meera", "Riya", "Kabir"];
    friends.push("Arjun");
    show(friends.length);
  11. 11.💾 What number does this code show?
    let notes = ["Music", "Sports", "Science"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
  12. 12.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 4;
    show(coins);
  13. 13.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Monsoon", "Ocean"];
    show(songs[2]);     (a) Sunrise (b) Monsoon (c) Rain (d) Ocean
  14. 14.💾 What number does this code show?
    let lives = 7;
    lives = lives - 2;
    lives = lives + 1;
    show(lives);
  15. 15.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Monsoon", "Ocean", "Rain", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Monsoon (b) Rain (c) Sunrise (d) Ocean
  16. 16.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
  17. 17.💾 What number does this code show?
    let friends = ["Aman", "Arjun", "Meera", "Riya"];
    friends.push("Kabir");
    show(friends.length);
  18. 18.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
  19. 19.True or false: your last game level fits saving on the phone. (a) False (b) True
  20. 20.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting
  21. 21.💾 What number does this code show?
    let notes = ["Hindi", "Science", "Sports"];
    notes.push("Art");
    show(notes.length);
  22. 22.Which of these fits saving on the phone? (a) the sound on/off setting (b) photos on two devices (c) a shared to-do list (d) a class leaderboard
  23. 23.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) your last game level (d) chat messages to friends
  24. 24.💾 What number does this code show?
    let coins = 5;
    coins = coins - 3;
    coins = coins + 4;
    show(coins);
  25. 25.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Science", "Sports", "Music", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Science (b) Music (c) Hindi (d) Sports
  26. 26.💾 What number does this code show?
    let points = 7;
    points = points - 5;
    points = points + 2;
    show(points);
  27. 27.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Kabir", "Meera"];
    show(friends[2]);     (a) Meera (b) Arjun (c) Kabir
  28. 28.💾 What number does this code show?
    let notes = ["Art", "Sports"];
    notes.push("Maths");
    show(notes.length);
  29. 29.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) photos on two devices (d) your last game level
  30. 30.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
  31. 31.💾 What number does this code show?
    let friends = ["Arjun", "Zoya", "Riya"];
    friends.push("Meera");
    show(friends.length);
  32. 32.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Arjun", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Arjun (b) Meera (c) Riya
  33. 33.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Music", "Hindi", "Sports", "Science"];
    show(notes[1]);     (a) Hindi (b) Music (c) Sports (d) Art
  34. 34.True or false: notes to read offline fits saving on the phone. (a) True (b) False
  35. 35.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
  36. 36.💾 What number does this code show?
    let songs = ["Sunrise", "Kites"];
    songs.push("Monsoon");
    show(songs.length);
  37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Ocean", "Rain", "Stars", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Rain (b) Stars (c) Ocean (d) Monsoon
  38. 38.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Monsoon", "Stars"];
    show(songs[2]);     (a) Kites (b) Monsoon (c) Stars (d) Sunrise
  39. 39.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
  40. 40.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone

Answer key

  1. a list
  2. Meera
  3. 5
  4. on the phone
  5. use it on any device
  6. 4
  7. Kabir
  8. in the cloud
  9. 7
  10. 5
  11. 5
  12. 6
  13. Monsoon
  14. 6
  15. Rain
  16. on the phone
  17. 5
  18. False
  19. True
  20. a named box for a value
  21. 4
  22. the sound on/off setting
  23. your last game level
  24. 6
  25. Music
  26. 4
  27. Meera
  28. 3
  29. photos on two devices
  30. False
  31. 4
  32. Arjun
  33. Music
  34. True
  35. False
  36. 3
  37. Stars
  38. Monsoon
  39. True
  40. on the phone

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