App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 638 · 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.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) a class leaderboard (d) notes to read offline
3. 3.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) photos on two devices (d) a draft you are typing
4. 4.💾 What number does this code show?
   let lives = 8;
   lives = lives - 3;
   lives = lives + 3;
   show(lives);
5. 5.💾 What number does this code show?
   let notes = ["Maths", "Hindi", "Sports", "Music"];
   notes.push("Art");
   notes.push("Science");
   show(notes.length);
6. 6.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
7. 7.💾 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
8. 8.💾 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
9. 9.💾 pop() takes off the last item. What does this code show?
   let friends = ["Arjun", "Aman", "Riya"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Arjun (b) Riya (c) Aman
10. 10.💾 What number does this code show?
    let lives = 7;
    lives = lives - 5;
    lives = lives + 3;
    show(lives);
11. 11.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Kabir", "Zoya", "Aman"];
    show(friends[1]); (a) Kabir (b) Zoya (c) Riya (d) Aman
12. 12.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Sports", "Hindi", "Science"];
    show(notes[3]); (a) Hindi (b) Art (c) Science (d) Sports
13. 13.💾 What is a variable? (a) a picture (b) a named box for a value (c) a type of screen (d) a phone setting
14. 14.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the phone is lost (c) the screen turns off (d) you send a message
15. 15.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) shrink the app (d) use it on any device
16. 16.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) chat messages to friends (d) a draft you are typing
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Art", "Maths"];
    show(notes[1]); (a) Maths (b) Art (c) Hindi
18. 18.💾 What number does this code show?
    let points = 8;
    points = points - 1;
    points = points + 1;
    show(points);
19. 19.💾 What number does this code show?
    let notes = ["Science", "Hindi"];
    notes.push("Maths");
    show(notes.length);
20. 20.💾 What number does this code show?
    let songs = ["Monsoon", "Ocean", "Sunrise"];
    songs.push("Rain");
    show(songs.length);
21. 21.Which of these fits saving on the phone? (a) your last game level (b) a class leaderboard (c) chat messages to friends (d) a shared to-do list
22. 22.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Stars", "Sunrise", "Kites", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Kites (c) Sunrise (d) Stars
23. 23.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Kites", "Rain", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Ocean (c) Rain (d) Monsoon
24. 24.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
25. 25.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) notes to read offline (d) a shared to-do list
26. 26.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Maths", "Art", "Science"];
    show(notes[3]); (a) Sports (b) Maths (c) Music (d) Art
27. 27.💾 What number does this code show?
    let songs = ["Monsoon", "Kites", "Rain", "Ocean"];
    songs.push("Stars");
    show(songs.length);
28. 28.💾 What number does this code show?
    let songs = ["Rain", "Ocean", "Stars", "Sunrise"];
    songs.push("Kites");
    show(songs.length);
29. 29.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
30. 30.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 4;
    show(coins);
31. 31.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon"];
    songs.push("Sunrise");
    show(songs.length);
32. 32.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
33. 33.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 1;
    show(coins);
34. 34.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
35. 35.💾 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
36. 36.Which of these fits saving in the cloud? (a) your last game level (b) chat messages to friends (c) the sound on/off setting (d) a draft you are typing
37. 37.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
39. 39.True or false: your last game level fits saving in the cloud. (a) False (b) True
40. 40.True or false: a draft you are typing fits saving on the phone. (a) False (b) True

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