App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 277 · 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.Which of these fits saving in the cloud? (a) notes to read offline (b) chat messages to friends (c) the sound on/off setting (d) your last game level
2. 2.💾 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
3. 3.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
5. 5.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
6. 6.💾 What number does this code show?
   let songs = ["Sunrise", "Rain", "Ocean"];
   songs.push("Kites");
   songs.push("Monsoon");
   show(songs.length);
7. 7.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
8. 8.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) photos on two devices (d) your last game level
10. 10.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
11. 11.💾 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
12. 12.💾 What number does this code show?
    let lives = 3;
    lives = lives - 3;
    lives = lives + 1;
    show(lives);
13. 13.Which of these fits saving on the phone? (a) chat messages to friends (b) notes to read offline (c) a class leaderboard (d) photos on two devices
14. 14.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Kabir", "Arjun", "Zoya", "Meera"];
    show(friends[2]); (a) Riya (b) Zoya (c) Kabir (d) Arjun
15. 15.💾 What number does this code show?
    let notes = ["Hindi", "Sports", "Music", "Maths"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
16. 16.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a picture (d) a named box for a value
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Sports", "Art", "Music", "Maths"];
    show(notes[2]); (a) Art (b) Music (c) Hindi (d) Sports
18. 18.Which of these fits saving on the phone? (a) a draft you are typing (b) a class leaderboard (c) a shared to-do list (d) chat messages to friends
19. 19.💾 What number does this code show?
    let songs = ["Monsoon", "Kites"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
20. 20.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
21. 21.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) use it on any device (d) shrink the app
22. 22.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
23. 23.💾 What number does this code show?
    let notes = ["Science", "Music"];
    notes.push("Sports");
    notes.push("Art");
    show(notes.length);
24. 24.True or false: your last game level fits saving in the cloud. (a) False (b) True
25. 25.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
26. 26.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) chat messages to friends (d) a shared to-do list
27. 27.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) you send a message (c) the app is closed (d) the screen turns off
28. 28.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
29. 29.Which of these fits saving on the phone? (a) the sound on/off setting (b) photos on two devices (c) chat messages to friends (d) a class leaderboard
30. 30.💾 What number does this code show?
    let score = 8;
    score = score - 1;
    score = score + 2;
    show(score);
31. 31.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Science", "Sports", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Science (c) Maths (d) Sports
32. 32.💾 What number does this code show?
    let points = 4;
    points = points - 3;
    points = points + 5;
    show(points);
33. 33.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Music", "Sports"];
    show(notes[0]); (a) Music (b) Art (c) Sports
34. 34.💾 What number does this code show?
    let coins = 9;
    coins = coins - 7;
    coins = coins + 2;
    show(coins);
35. 35.Which of these fits saving in the cloud? (a) a draft you are typing (b) a class leaderboard (c) the sound on/off setting (d) notes to read offline
36. 36.💾 What number does this code show?
    let score = 9;
    score = score - 4;
    score = score + 3;
    show(score);
37. 37.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
38. 38.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Monsoon"];
    show(songs[0]); (a) Sunrise (b) Rain (c) Monsoon
39. 39.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Kites", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Stars
40. 40.True or false: photos on two devices fits saving in the cloud. (a) False (b) True

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