App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 952 · 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: notes to read offline fits saving on the phone. (a) False (b) True
2. 2.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.💾 Which can hold many values in order? (a) a button (b) a single number (c) a list (d) a switch
4. 4.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.Which of these fits saving in the cloud? (a) chat messages to friends (b) the sound on/off setting (c) a draft you are typing (d) notes to read offline
6. 6.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
7. 7.💾 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
8. 8.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the screen turns off (d) the phone is lost
9. 9.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
10. 10.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
11. 11.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
12. 12.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) photos on two devices (d) chat messages to friends
13. 13.💾 What is a variable? (a) a picture (b) a type of screen (c) a named box for a value (d) a phone setting
14. 14.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
15. 15.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean"];
    songs.push("Monsoon");
    show(songs.length);
16. 16.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Music", "Science", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Art (c) Music (d) Science
17. 17.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Meera", "Riya", "Aman", "Kabir"];
    show(friends[0]); (a) Arjun (b) Riya (c) Meera (d) Aman
18. 18.💾 What number does this code show?
    let friends = ["Zoya", "Riya"];
    friends.push("Meera");
    friends.push("Arjun");
    show(friends.length);
19. 19.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) a draft you are typing
20. 20.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Stars", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Kites (c) Monsoon
21. 21.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Rain", "Ocean", "Stars"];
    show(songs[4]); (a) Sunrise (b) Rain (c) Stars (d) Kites
22. 22.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
23. 23.💾 What number does this code show?
    let friends = ["Meera", "Zoya"];
    friends.push("Arjun");
    show(friends.length);
24. 24.💾 What number does this code show?
    let stars = 4;
    stars = stars - 3;
    stars = stars + 5;
    show(stars);
25. 25.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Riya", "Aman", "Kabir", "Meera"];
    show(friends[2]); (a) Aman (b) Riya (c) Zoya (d) Kabir
26. 26.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 10 (c) 0 (d) 1
27. 27.💾 What number does this code show?
    let songs = ["Kites", "Monsoon", "Stars", "Ocean"];
    songs.push("Rain");
    show(songs.length);
28. 28.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Music (c) Science
29. 29.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Riya", "Arjun", "Meera"];
    show(friends[0]); (a) Aman (b) Arjun (c) Riya (d) Meera
30. 30.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) a cloud backup (d) data saved on the phone
31. 31.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
32. 32.💾 What number does this code show?
    let notes = ["Hindi", "Maths", "Music", "Science"];
    notes.push("Art");
    notes.push("Sports");
    show(notes.length);
33. 33.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) the sound on/off setting (d) a class leaderboard
34. 34.💾 What number does this code show?
    let notes = ["Sports", "Art"];
    notes.push("Science");
    notes.push("Music");
    show(notes.length);
35. 35.💾 What number does this code show?
    let lives = 4;
    lives = lives - 1;
    lives = lives + 4;
    show(lives);
36. 36.💾 What number does this code show?
    let coins = 4;
    coins = coins - 2;
    coins = coins + 2;
    show(coins);
37. 37.Which of these fits saving in the cloud? (a) photos on two devices (b) the sound on/off setting (c) your last game level (d) notes to read offline
38. 38.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
39. 39.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
40. 40.💾 What number does this code show?
    let stars = 8;
    stars = stars - 3;
    stars = stars + 5;
    show(stars);

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