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App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 831 · 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 does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Sunrise"];
    show(songs[2]);     (a) Sunrise (b) Kites (c) Rain
  2. 2.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) skip the internet (d) never need a password
  3. 3.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Art", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Art (b) Science (c) Hindi
  4. 4.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Zoya", "Meera", "Riya"];
    show(friends[2]);     (a) Riya (b) Aman (c) Meera (d) Zoya
  5. 5.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Music", "Art"];
    show(notes[1]);     (a) Science (b) Art (c) Music
  6. 6.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Arjun", "Riya", "Zoya", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Zoya (b) Riya (c) Aman (d) Arjun
  7. 7.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Stars", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Stars (b) Kites (c) Sunrise
  8. 8.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) a shared to-do list (d) the sound on/off setting
  9. 9.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a class leaderboard (d) a shared to-do list
  10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Kites", "Stars"];
    show(songs[1]);     (a) Stars (b) Kites (c) Ocean
  11. 11.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
  12. 12.💾 What number does this code show?
    let points = 9;
    points = points - 6;
    points = points + 2;
    show(points);
  13. 13.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Zoya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Riya (b) Zoya (c) Aman
  14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Kites", "Stars", "Ocean"];
    show(songs[0]);     (a) Kites (b) Monsoon (c) Stars (d) Ocean
  15. 15.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
  16. 16.True or false: notes to read offline fits saving on the phone. (a) False (b) True
  17. 17.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) chat messages to friends (d) your last game level
  18. 18.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Riya", "Zoya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]);     (a) Zoya (b) Kabir (c) Riya (d) Meera
  19. 19.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
  20. 20.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Rain", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]);     (a) Ocean (b) Rain (c) Sunrise
  21. 21.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
  22. 22.💾 What number does this code show?
    let friends = ["Arjun", "Riya", "Zoya", "Kabir"];
    friends.push("Aman");
    show(friends.length);
  23. 23.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Riya", "Arjun"];
    show(friends[0]);     (a) Riya (b) Arjun (c) Aman (d) Meera
  24. 24.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a picture (d) a type of screen
  25. 25.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 5;
    show(coins);
  26. 26.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
  27. 27.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Hindi", "Science"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Hindi (b) Science (c) Maths
  28. 28.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Science", "Art"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Art (b) Science (c) Sports
  29. 29.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
  30. 30.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
  31. 31.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
  32. 32.💾 What number does this code show?
    let songs = ["Ocean", "Rain"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
  33. 33.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
  34. 34.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Maths", "Art"];
    show(notes[1]);     (a) Art (b) Maths (c) Science
  35. 35.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
  36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Meera"];
    show(friends[1]);     (a) Kabir (b) Meera (c) Aman
  37. 37.💾 What number does this code show?
    let lives = 8;
    lives = lives - 5;
    lives = lives + 3;
    show(lives);
  38. 38.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 4;
    show(score);
  39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Maths", "Sports", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Music (b) Sports (c) Science (d) Maths
  40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Sports", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]);     (a) Maths (b) Music (c) Sports

Answer key

  1. Sunrise
  2. use it on any device
  3. Art
  4. Meera
  5. Music
  6. Zoya
  7. Stars
  8. a shared to-do list
  9. your last game level
  10. Kites
  11. False
  12. 5
  13. Zoya
  14. Monsoon
  15. in the cloud
  16. True
  17. chat messages to friends
  18. Zoya
  19. on the phone
  20. Rain
  21. True
  22. 5
  23. Aman
  24. a named box for a value
  25. 7
  26. True
  27. Hindi
  28. Science
  29. on the phone
  30. in the cloud
  31. False
  32. 4
  33. in the cloud
  34. Maths
  35. True
  36. Kabir
  37. 6
  38. 5
  39. Sports
  40. Sports

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