App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 925 · 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.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
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.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a shared chat (d) a cloud backup
4. 4.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Maths", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Science (c) Maths
5. 5.Which of these fits saving in the cloud? (a) your last game level (b) photos on two devices (c) a draft you are typing (d) notes to read offline
6. 6.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
7. 7.💾 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
8. 8.💾 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
9. 9.💾 What does this code show? (Positions start at 0.)
   let notes = ["Maths", "Art", "Science", "Music", "Sports"];
   show(notes[4]); (a) Sports (b) Maths (c) Science (d) Art
10. 10.True or false: notes to read offline fits saving on the phone. (a) False (b) True
11. 11.💾 Which can hold many values in order? (a) a list (b) a button (c) a single number (d) a switch
12. 12.💾 What number does this code show?
    let notes = ["Hindi", "Sports", "Music", "Art"];
    notes.push("Maths");
    show(notes.length);
13. 13.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) skip the internet (d) use it on any device
14. 14.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
15. 15.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
16. 16.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
17. 17.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
18. 18.Which of these fits saving on the phone? (a) your last game level (b) photos on two devices (c) a class leaderboard (d) chat messages to friends
19. 19.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Riya", "Aman"];
    show(friends[0]); (a) Riya (b) Arjun (c) Aman
20. 20.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Stars", "Monsoon", "Kites"];
    show(songs[1]); (a) Monsoon (b) Stars (c) Sunrise (d) Rain
21. 21.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) photos on two devices (d) a draft you are typing
22. 22.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
23. 23.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Art (c) Music
24. 24.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
25. 25.💾 What number does this code show?
    let lives = 6;
    lives = lives - 5;
    lives = lives + 3;
    show(lives);
26. 26.💾 What number does this code show?
    let songs = ["Kites", "Sunrise", "Stars", "Monsoon"];
    songs.push("Ocean");
    show(songs.length);
27. 27.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Zoya"];
    show(friends[0]); (a) Riya (b) Zoya (c) Arjun
28. 28.💾 What number does this code show?
    let notes = ["Music", "Maths", "Science", "Sports"];
    notes.push("Hindi");
    show(notes.length);
29. 29.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
30. 30.💾 What is a variable? (a) a picture (b) a type of screen (c) a named box for a value (d) a phone setting
31. 31.💾 What number does this code show?
    let notes = ["Maths", "Art"];
    notes.push("Hindi");
    notes.push("Music");
    show(notes.length);
32. 32.💾 What number does this code show?
    let score = 5;
    score = score - 3;
    score = score + 1;
    show(score);
33. 33.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a draft you are typing (d) chat messages to friends
34. 34.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Rain"];
    show(songs[0]); (a) Rain (b) Sunrise (c) Kites
35. 35.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a shared to-do list (c) a draft you are typing (d) notes to read offline
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon", "Kites", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Kites (c) Sunrise (d) Rain
37. 37.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Ocean"];
    show(songs[2]); (a) Ocean (b) Monsoon (c) Rain
38. 38.💾 What number does this code show?
    let friends = ["Riya", "Zoya"];
    friends.push("Meera");
    friends.push("Kabir");
    show(friends.length);
39. 39.💾 What number does this code show?
    let notes = ["Art", "Music", "Hindi"];
    notes.push("Maths");
    notes.push("Science");
    show(notes.length);
40. 40.True or false: a class leaderboard fits saving on the phone. (a) False (b) True

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