App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 21 · 40 questions

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.

1. 1.💾 pop() takes off the last item. What does this code show?
   let songs = ["Kites", "Rain", "Stars", "Sunrise"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Sunrise (b) Kites (c) Rain (d) Stars
2. 2.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.💾 What number does this code show?
   let stars = 3;
   stars = stars - 1;
   stars = stars + 2;
   show(stars);
4. 4.Which of these fits saving on the phone? (a) the sound on/off setting (b) chat messages to friends (c) a shared to-do list (d) photos on two devices
5. 5.💾 What number does this code show?
   let notes = ["Art", "Sports", "Science", "Hindi"];
   notes.push("Music");
   notes.push("Maths");
   show(notes.length);
6. 6.💾 What number does this code show?
   let songs = ["Ocean", "Sunrise"];
   songs.push("Kites");
   show(songs.length);
7. 7.💾 What number does this code show?
   let coins = 5;
   coins = coins - 2;
   coins = coins + 2;
   show(coins);
8. 8.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.True or false: your last game level fits saving in the cloud. (a) True (b) False
10. 10.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
11. 11.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Ocean (c) Sunrise
12. 12.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
13. 13.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
14. 14.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) a class leaderboard (d) the sound on/off setting
15. 15.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
16. 16.💾 What number does this code show?
    let songs = ["Ocean", "Stars"];
    songs.push("Sunrise");
    songs.push("Kites");
    show(songs.length);
17. 17.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) notes to read offline (d) chat messages to friends
18. 18.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Sunrise", "Kites"];
    songs.push("Stars");
    show(songs.length);
19. 19.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
21. 21.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
22. 22.💾 What number does this code show?
    let songs = ["Ocean", "Sunrise", "Monsoon"];
    songs.push("Kites");
    songs.push("Rain");
    show(songs.length);
23. 23.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Kites", "Sunrise"];
    show(songs[1]); (a) Sunrise (b) Kites (c) Stars
24. 24.💾 What number does this code show?
    let notes = ["Science", "Music"];
    notes.push("Sports");
    show(notes.length);
25. 25.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Stars", "Sunrise", "Kites"];
    show(songs[4]); (a) Stars (b) Rain (c) Kites (d) Monsoon
26. 26.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Maths", "Sports"];
    show(notes[2]); (a) Maths (b) Music (c) Sports
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.💾 What number does this code show?
    let notes = ["Science", "Art"];
    notes.push("Sports");
    notes.push("Music");
    show(notes.length);
29. 29.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Zoya", "Meera", "Arjun", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Kabir (c) Zoya (d) Arjun
30. 30.💾 What number does this code show?
    let notes = ["Hindi", "Science", "Maths", "Sports"];
    notes.push("Art");
    show(notes.length);
31. 31.Which of these fits saving on the phone? (a) your last game level (b) chat messages to friends (c) a class leaderboard (d) photos on two devices
32. 32.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a shared to-do list (d) notes to read offline
33. 33.Which of these fits saving in the cloud? (a) a shared to-do list (b) your last game level (c) a draft you are typing (d) the sound on/off setting
34. 34.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 3;
    show(stars);
35. 35.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
36. 36.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Music", "Sports"];
    show(notes[2]); (a) Music (b) Sports (c) Science
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Hindi", "Music", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Hindi (c) Maths (d) Science
38. 38.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
39. 39.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 3;
    show(lives);
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Ocean", "Rain"];
    show(songs[0]); (a) Ocean (b) Rain (c) Stars

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