App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 268 · 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 your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) shrink the app (c) never need a password (d) use it on any device
3. 3.💾 What number does this code show?
   let notes = ["Maths", "Art", "Music"];
   notes.push("Hindi");
   notes.push("Sports");
   show(notes.length);
4. 4.💾 What number does this code show?
   let coins = 6;
   coins = coins - 1;
   coins = coins + 4;
   show(coins);
5. 5.💾 What number does this code show?
   let friends = ["Zoya", "Arjun"];
   friends.push("Riya");
   show(friends.length);
6. 6.💾 What does this code show? (Positions start at 0.)
   let songs = ["Rain", "Stars", "Ocean"];
   show(songs[0]); (a) Ocean (b) Stars (c) Rain
7. 7.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 1 (d) 2
8. 8.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Maths", "Sports", "Art", "Hindi"];
   show(notes[1]); (a) Sports (b) Science (c) Art (d) Maths
9. 9.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
10. 10.💾 What number does this code show?
    let stars = 5;
    stars = stars - 2;
    stars = stars + 5;
    show(stars);
11. 11.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon"];
    songs.push("Rain");
    show(songs.length);
12. 12.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Kites", "Monsoon", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Kites (c) Sunrise (d) Ocean
13. 13.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) a class leaderboard (d) chat messages to friends
14. 14.💾 What number does this code show?
    let points = 5;
    points = points - 5;
    points = points + 4;
    show(points);
15. 15.💾 What number does this code show?
    let friends = ["Arjun", "Kabir", "Riya", "Aman"];
    friends.push("Meera");
    show(friends.length);
16. 16.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) the sound on/off setting (d) a class leaderboard
17. 17.💾 What number does this code show?
    let score = 6;
    score = score - 6;
    score = score + 1;
    show(score);
18. 18.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
19. 19.💾 What number does this code show?
    let friends = ["Kabir", "Zoya"];
    friends.push("Meera");
    show(friends.length);
20. 20.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 5;
    show(score);
21. 21.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
22. 22.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Art (c) Music
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Hindi", "Music", "Art"];
    show(notes[0]); (a) Hindi (b) Sports (c) Music (d) Art
24. 24.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
25. 25.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a class leaderboard (c) a draft you are typing (d) notes to read offline
26. 26.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
27. 27.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Kites (c) Ocean
28. 28.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
29. 29.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
30. 30.💾 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
31. 31.Which of these fits saving on the phone? (a) your last game level (b) a shared to-do list (c) chat messages to friends (d) a class leaderboard
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Stars", "Sunrise", "Kites"];
    show(songs[1]); (a) Kites (b) Stars (c) Sunrise (d) Ocean
33. 33.💾 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
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Aman", "Meera", "Arjun", "Riya"];
    show(friends[4]); (a) Zoya (b) Riya (c) Aman (d) Meera
35. 35.Which of these fits saving in the cloud? (a) a shared to-do list (b) your last game level (c) notes to read offline (d) the sound on/off setting
36. 36.💾 What number does this code show?
    let friends = ["Riya", "Kabir"];
    friends.push("Aman");
    show(friends.length);
37. 37.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
38. 38.💾 What number does this code show?
    let friends = ["Arjun", "Riya", "Zoya", "Kabir"];
    friends.push("Meera");
    friends.push("Aman");
    show(friends.length);
39. 39.💾 What number does this code show?
    let stars = 9;
    stars = stars - 4;
    stars = stars + 2;
    show(stars);
40. 40.💾 What number does this code show?
    let notes = ["Sports", "Art", "Hindi"];
    notes.push("Maths");
    notes.push("Music");
    show(notes.length);

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