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App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 205 · 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.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Science"];
    notes.push("Sports");
    notes.push("Music");
    show(notes.length);
  2. 2.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
  3. 3.💾 What is a variable? (a) a phone setting (b) a picture (c) a type of screen (d) a named box for a value
  4. 4.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Rain", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Stars (b) Sunrise (c) Rain (d) Monsoon
  5. 5.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Ocean", "Monsoon", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Monsoon (b) Ocean (c) Sunrise (d) Kites
  6. 6.Which of these fits saving on the phone? (a) your last game level (b) a class leaderboard (c) chat messages to friends (d) photos on two devices
  7. 7.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) chat messages to friends (d) a draft you are typing
  8. 8.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Aman", "Meera", "Kabir", "Zoya"];
    show(friends[2]);     (a) Arjun (b) Aman (c) Meera (d) Kabir
  9. 9.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Aman", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Riya (b) Kabir (c) Aman
  10. 10.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
  11. 11.💾 What number does this code show?
    let friends = ["Riya", "Arjun", "Aman"];
    friends.push("Kabir");
    show(friends.length);
  12. 12.True or false: notes to read offline fits saving on the phone. (a) True (b) False
  13. 13.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Arjun", "Meera"];
    show(friends[3]);     (a) Arjun (b) Meera (c) Aman (d) Riya
  14. 14.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) the sound on/off setting (d) a shared to-do list
  15. 15.💾 What number does this code show?
    let lives = 6;
    lives = lives - 6;
    lives = lives + 3;
    show(lives);
  16. 16.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
  17. 17.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
  18. 18.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Aman", "Arjun", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Arjun (b) Riya (c) Aman (d) Zoya
  19. 19.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) notes to read offline (d) photos on two devices
  20. 20.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
  21. 21.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
  22. 22.💾 What number does this code show?
    let friends = ["Zoya", "Aman"];
    friends.push("Kabir");
    show(friends.length);
  23. 23.💾 Which can hold many values in order? (a) a list (b) a button (c) a switch (d) a single number
  24. 24.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
  25. 25.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Science", "Music", "Art"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Science (b) Sports (c) Music (d) Hindi
  26. 26.💾 What number does this code show?
    let notes = ["Music", "Sports", "Science"];
    notes.push("Hindi");
    show(notes.length);
  27. 27.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
  28. 28.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a cloud backup (d) a shared chat
  29. 29.💾 What number does this code show?
    let songs = ["Ocean", "Kites"];
    songs.push("Rain");
    songs.push("Monsoon");
    show(songs.length);
  30. 30.💾 What number does this code show?
    let notes = ["Hindi", "Maths"];
    notes.push("Art");
    notes.push("Sports");
    show(notes.length);
  31. 31.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
  32. 32.💾 What number does this code show?
    let score = 4;
    score = score - 2;
    score = score + 4;
    show(score);
  33. 33.💾 What number does this code show?
    let friends = ["Kabir", "Zoya", "Arjun"];
    friends.push("Riya");
    show(friends.length);
  34. 34.💾 What number does this code show?
    let friends = ["Aman", "Riya", "Kabir"];
    friends.push("Arjun");
    friends.push("Zoya");
    show(friends.length);
  35. 35.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Kabir", "Meera", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Aman (b) Meera (c) Zoya (d) Kabir
  36. 36.💾 What number does this code show?
    let notes = ["Maths", "Art", "Sports"];
    notes.push("Science");
    show(notes.length);
  37. 37.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
  38. 38.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Kites", "Rain", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Rain (b) Sunrise (c) Kites (d) Ocean
  39. 39.💾 What number does this code show?
    let friends = ["Zoya", "Kabir", "Arjun"];
    friends.push("Aman");
    friends.push("Meera");
    show(friends.length);
  40. 40.True or false: your last game level fits saving in the cloud. (a) False (b) True

Answer key

  1. 5
  2. on the phone
  3. a named box for a value
  4. Rain
  5. Monsoon
  6. your last game level
  7. chat messages to friends
  8. Meera
  9. Aman
  10. True
  11. 4
  12. True
  13. Meera
  14. the sound on/off setting
  15. 3
  16. in the cloud
  17. True
  18. Riya
  19. notes to read offline
  20. True
  21. False
  22. 3
  23. a list
  24. True
  25. Music
  26. 4
  27. on the phone
  28. data saved on the phone
  29. 4
  30. 4
  31. in the cloud
  32. 6
  33. 4
  34. 5
  35. Meera
  36. 4
  37. True
  38. Rain
  39. 5
  40. False

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