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App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 873 · 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 single number (c) a switch (d) a button
  2. 2.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
  3. 3.💾 What number does this code show?
    let notes = ["Art", "Sports"];
    notes.push("Hindi");
    notes.push("Science");
    show(notes.length);
  4. 4.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) a shared to-do list (d) notes to read offline
  5. 5.💾 What number does this code show?
    let coins = 4;
    coins = coins - 2;
    coins = coins + 5;
    show(coins);
  6. 6.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
  7. 7.💾 Which works with no internet at all? (a) a shared chat (b) a cloud backup (c) a cloud leaderboard (d) data saved on the phone
  8. 8.💾 What number does this code show?
    let coins = 9;
    coins = coins - 3;
    coins = coins + 3;
    show(coins);
  9. 9.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
  10. 10.💾 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
  11. 11.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Kites", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Sunrise (b) Rain (c) Stars (d) Kites
  12. 12.💾 What number does this code show?
    let points = 4;
    points = points - 1;
    points = points + 4;
    show(points);
  13. 13.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) your last game level (d) photos on two devices
  14. 14.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a picture (d) a named box for a value
  15. 15.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) never need a password (d) skip the internet
  16. 16.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the phone is lost (d) the app is closed
  17. 17.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
  18. 18.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) photos on two devices (d) a draft you are typing
  19. 19.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
  20. 20.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
  21. 21.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
  22. 22.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) your last game level (d) chat messages to friends
  23. 23.💾 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
  24. 24.💾 What number does this code show?
    let score = 7;
    score = score - 7;
    score = score + 3;
    show(score);
  25. 25.True or false: photos on two devices fits saving on the phone. (a) True (b) False
  26. 26.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
  27. 27.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) notes to read offline (d) a class leaderboard
  28. 28.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Rain", "Sunrise", "Ocean", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Sunrise (b) Ocean (c) Rain (d) Stars
  29. 29.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
  30. 30.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Meera", "Zoya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Zoya (b) Meera (c) Aman (d) Riya
  31. 31.💾 What number does this code show?
    let points = 8;
    points = points - 8;
    points = points + 2;
    show(points);
  32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Monsoon", "Ocean", "Sunrise"];
    show(songs[3]);     (a) Kites (b) Sunrise (c) Monsoon (d) Ocean
  33. 33.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Ocean", "Rain", "Kites", "Stars"];
    show(songs[1]);     (a) Kites (b) Ocean (c) Rain (d) Monsoon
  34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Kites", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Monsoon (b) Rain (c) Kites (d) Sunrise
  35. 35.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Arjun", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Aman (b) Zoya (c) Arjun (d) Riya
  36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Music", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Sports (b) Maths (c) Music (d) Hindi
  37. 37.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
  38. 38.💾 What number does this code show?
    let stars = 7;
    stars = stars - 4;
    stars = stars + 1;
    show(stars);
  39. 39.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) a class leaderboard (d) a draft you are typing
  40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Kabir", "Meera", "Aman", "Riya"];
    show(friends[1]);     (a) Zoya (b) Aman (c) Meera (d) Kabir

Answer key

  1. a list
  2. on the phone
  3. 4
  4. a shared to-do list
  5. 7
  6. 0
  7. data saved on the phone
  8. 9
  9. on the phone
  10. in the cloud
  11. Kites
  12. 7
  13. your last game level
  14. a named box for a value
  15. use it on any device
  16. the phone is lost
  17. True
  18. photos on two devices
  19. True
  20. the sound on/off setting
  21. False
  22. chat messages to friends
  23. on the phone
  24. 3
  25. False
  26. in the cloud
  27. a class leaderboard
  28. Ocean
  29. in the cloud
  30. Zoya
  31. 2
  32. Sunrise
  33. Ocean
  34. Kites
  35. Arjun
  36. Music
  37. True
  38. 4
  39. a draft you are typing
  40. Kabir

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