App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 898 · 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 the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.💾 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
4. 4.💾 pop() takes off the last item. What does this code show?
   let notes = ["Music", "Art", "Sports", "Maths", "Science"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Music (c) Sports (d) Maths
5. 5.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) notes to read offline (d) chat messages to friends
6. 6.💾 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
7. 7.💾 What number does this code show?
   let notes = ["Maths", "Sports"];
   notes.push("Art");
   show(notes.length);
8. 8.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
9. 9.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 shared to-do list
10. 10.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) notes to read offline (d) a class leaderboard
11. 11.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
12. 12.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 3;
    show(stars);
13. 13.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Monsoon", "Rain", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Sunrise (c) Kites (d) Rain
14. 14.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
15. 15.💾 What number does this code show?
    let stars = 4;
    stars = stars - 4;
    stars = stars + 4;
    show(stars);
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Aman", "Riya", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Arjun (c) Riya (d) Aman
17. 17.💾 What number does this code show?
    let songs = ["Monsoon", "Ocean"];
    songs.push("Kites");
    show(songs.length);
18. 18.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 1 (d) 10
19. 19.💾 What number does this code show?
    let songs = ["Ocean", "Rain", "Stars", "Sunrise"];
    songs.push("Monsoon");
    show(songs.length);
20. 20.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a picture (d) a type of screen
21. 21.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
22. 22.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Sports", "Music", "Hindi"];
    show(notes[4]); (a) Art (b) Maths (c) Sports (d) Hindi
23. 23.💾 What number does this code show?
    let friends = ["Zoya", "Riya"];
    friends.push("Kabir");
    friends.push("Meera");
    show(friends.length);
24. 24.💾 What number does this code show?
    let stars = 8;
    stars = stars - 8;
    stars = stars + 5;
    show(stars);
25. 25.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Monsoon", "Stars", "Ocean", "Kites"];
    show(songs[3]); (a) Rain (b) Ocean (c) Stars (d) Monsoon
26. 26.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Arjun", "Meera", "Kabir"];
    show(friends[2]); (a) Meera (b) Arjun (c) Aman (d) Kabir
27. 27.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) the sound on/off setting (d) a shared to-do list
28. 28.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
29. 29.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
30. 30.Which of these fits saving on the phone? (a) a draft you are typing (b) chat messages to friends (c) a shared to-do list (d) a class leaderboard
31. 31.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
32. 32.💾 What number does this code show?
    let notes = ["Sports", "Maths"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
33. 33.💾 What number does this code show?
    let songs = ["Sunrise", "Stars"];
    songs.push("Monsoon");
    show(songs.length);
34. 34.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud backup (c) a shared chat (d) a cloud leaderboard
35. 35.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Kites", "Ocean"];
    show(songs[0]); (a) Ocean (b) Rain (c) Kites
36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Sports", "Science", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Hindi (c) Sports (d) Art
37. 37.💾 What number does this code show?
    let notes = ["Art", "Sports"];
    notes.push("Hindi");
    notes.push("Music");
    show(notes.length);
38. 38.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Music", "Science", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Maths (c) Hindi (d) Music
40. 40.True or false: a draft you are typing fits saving on the phone. (a) True (b) False

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