App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 394 · 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", "Meera", "Riya"];
   friends.push("Kabir");
   friends.push("Aman");
   show(friends.length);
2. 2.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
3. 3.💾 pop() takes off the last item. What does this code show?
   let notes = ["Sports", "Art", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Art (c) Music
4. 4.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
5. 5.💾 What does this code show? (Positions start at 0.)
   let friends = ["Zoya", "Meera", "Kabir"];
   show(friends[0]); (a) Meera (b) Zoya (c) Kabir
6. 6.💾 What number does this code show?
   let coins = 7;
   coins = coins - 7;
   coins = coins + 1;
   show(coins);
7. 7.💾 What number does this code show?
   let points = 7;
   points = points - 6;
   points = points + 1;
   show(points);
8. 8.Which of these fits saving in the cloud? (a) a class leaderboard (b) the sound on/off setting (c) your last game level (d) notes to read offline
9. 9.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) photos on two devices (d) a draft you are typing
10. 10.💾 What number does this code show?
    let songs = ["Rain", "Kites"];
    songs.push("Sunrise");
    songs.push("Ocean");
    show(songs.length);
11. 11.💾 What is a variable? (a) a phone setting (b) a picture (c) a type of screen (d) a named box for a value
12. 12.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
13. 13.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Ocean", "Sunrise"];
    show(songs[0]); (a) Ocean (b) Stars (c) Sunrise
14. 14.💾 What number does this code show?
    let friends = ["Riya", "Aman"];
    friends.push("Meera");
    friends.push("Arjun");
    show(friends.length);
15. 15.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
16. 16.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
17. 17.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Rain", "Kites", "Sunrise"];
    show(songs[1]); (a) Kites (b) Sunrise (c) Rain (d) Stars
18. 18.True or false: photos on two devices fits saving on the phone. (a) False (b) True
19. 19.💾 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
20. 20.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) notes to read offline (d) a class leaderboard
21. 21.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) the sound on/off setting (d) a shared to-do list
22. 22.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) a draft you are typing (d) chat messages to friends
23. 23.💾 What number does this code show?
    let songs = ["Monsoon", "Stars", "Kites", "Sunrise"];
    songs.push("Ocean");
    show(songs.length);
24. 24.💾 What number does this code show?
    let friends = ["Zoya", "Meera", "Kabir", "Arjun"];
    friends.push("Riya");
    show(friends.length);
25. 25.💾 What number does this code show?
    let songs = ["Kites", "Sunrise", "Monsoon", "Rain"];
    songs.push("Ocean");
    show(songs.length);
26. 26.💾 What number does this code show?
    let songs = ["Stars", "Monsoon"];
    songs.push("Rain");
    songs.push("Sunrise");
    show(songs.length);
27. 27.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) you send a message (c) the app is closed (d) the phone is lost
28. 28.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) use it on any device (d) shrink the app
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Ocean", "Monsoon", "Kites"];
    show(songs[2]); (a) Rain (b) Ocean (c) Sunrise (d) Monsoon
30. 30.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
31. 31.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
32. 32.Which of these fits saving in the cloud? (a) chat messages to friends (b) a draft you are typing (c) the sound on/off setting (d) your last game level
33. 33.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Sunrise", "Ocean", "Monsoon", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Sunrise (c) Ocean (d) Monsoon
35. 35.💾 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
36. 36.True or false: notes to read offline fits saving on the phone. (a) False (b) True
37. 37.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
38. 38.💾 What number does this code show?
    let songs = ["Kites", "Ocean"];
    songs.push("Monsoon");
    songs.push("Rain");
    show(songs.length);
39. 39.💾 What number does this code show?
    let points = 4;
    points = points - 4;
    points = points + 5;
    show(points);
40. 40.💾 What number does this code show?
    let stars = 7;
    stars = stars - 2;
    stars = stars + 1;
    show(stars);

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