App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 694 · 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.💾 What number does this code show?
   let friends = ["Arjun", "Zoya", "Riya"];
   friends.push("Aman");
   show(friends.length);
2. 2.💾 Where should the app save notes to read offline: 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) skip the internet (b) shrink the app (c) use it on any device (d) never need a password
4. 4.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
6. 6.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
7. 7.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) chat messages to friends (d) a draft you are typing
8. 8.💾 What number does this code show?
   let score = 3;
   score = score - 3;
   score = score + 4;
   show(score);
9. 9.💾 What number does this code show?
   let songs = ["Stars", "Ocean", "Rain"];
   songs.push("Monsoon");
   songs.push("Sunrise");
   show(songs.length);
10. 10.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Kabir", "Aman"];
    show(friends[3]); (a) Aman (b) Kabir (c) Arjun (d) Riya
11. 11.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
12. 12.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.💾 What number does this code show?
    let songs = ["Monsoon", "Kites"];
    songs.push("Rain");
    songs.push("Sunrise");
    show(songs.length);
14. 14.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
15. 15.True or false: notes to read offline fits saving on the phone. (a) True (b) False
16. 16.💾 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
17. 17.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) the sound on/off setting (d) photos on two devices
18. 18.💾 What number does this code show?
    let notes = ["Sports", "Hindi"];
    notes.push("Maths");
    show(notes.length);
19. 19.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
20. 20.💾 What number does this code show?
    let score = 8;
    score = score - 6;
    score = score + 3;
    show(score);
21. 21.True or false: your last game level fits saving in the cloud. (a) False (b) True
22. 22.💾 What number does this code show?
    let songs = ["Kites", "Sunrise", "Monsoon", "Stars"];
    songs.push("Rain");
    songs.push("Ocean");
    show(songs.length);
23. 23.💾 What number does this code show?
    let stars = 5;
    stars = stars - 2;
    stars = stars + 5;
    show(stars);
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Science", "Music"];
    show(notes[0]); (a) Science (b) Music (c) Hindi (d) Maths
25. 25.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Kites", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Sunrise (c) Kites
26. 26.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) you send a message (c) the screen turns off (d) the phone is lost
27. 27.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Art", "Science", "Maths"];
    show(notes[2]); (a) Maths (b) Art (c) Science (d) Music
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Maths", "Sports", "Art"];
    show(notes[1]); (a) Music (b) Maths (c) Sports (d) Science
30. 30.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon", "Kites", "Rain"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
31. 31.💾 What number does this code show?
    let notes = ["Science", "Art"];
    notes.push("Music");
    show(notes.length);
32. 32.💾 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
33. 33.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Kites", "Stars"];
    show(songs[2]); (a) Kites (b) Stars (c) Ocean
34. 34.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
35. 35.💾 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
36. 36.True or false: your last game level fits saving on the phone. (a) False (b) True
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Monsoon (c) Rain (d) Sunrise
38. 38.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Rain (c) Monsoon
39. 39.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
40. 40.True or false: a class leaderboard fits saving on the phone. (a) True (b) False

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