App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 71 · 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: a class leaderboard fits saving on the phone. (a) False (b) True
2. 2.💾 What number does this code show?
   let stars = 5;
   stars = stars - 3;
   stars = stars + 1;
   show(stars);
3. 3.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a shared chat (d) a cloud backup
4. 4.💾 pop() takes off the last item. What does this code show?
   let notes = ["Maths", "Hindi", "Art", "Science", "Sports"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Art (c) Science (d) Hindi
5. 5.💾 What number does this code show?
   let stars = 5;
   stars = stars - 4;
   stars = stars + 3;
   show(stars);
6. 6.💾 What number does this code show?
   let score = 6;
   score = score - 1;
   score = score + 1;
   show(score);
7. 7.💾 What number does this code show?
   let notes = ["Maths", "Science", "Music", "Art"];
   notes.push("Sports");
   show(notes.length);
8. 8.💾 What does this code show? (Positions start at 0.)
   let friends = ["Zoya", "Riya", "Meera", "Aman"];
   show(friends[1]); (a) Riya (b) Meera (c) Zoya (d) Aman
9. 9.💾 What number does this code show?
   let score = 9;
   score = score - 8;
   score = score + 4;
   show(score);
10. 10.Which of these fits saving in the cloud? (a) the sound on/off setting (b) chat messages to friends (c) notes to read offline (d) a draft you are typing
11. 11.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
12. 12.💾 What is a variable? (a) a phone setting (b) a picture (c) a named box for a value (d) a type of screen
13. 13.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) a shared to-do list
14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Stars", "Sunrise", "Kites", "Rain"];
    show(songs[0]); (a) Sunrise (b) Stars (c) Ocean (d) Kites
15. 15.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the phone is lost (c) the app is closed (d) you send a message
16. 16.💾 Where should the app save chat messages to friends: 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 shared to-do list (b) photos on two devices (c) your last game level (d) a class leaderboard
18. 18.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
19. 19.💾 What number does this code show?
    let points = 8;
    points = points - 4;
    points = points + 3;
    show(points);
20. 20.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) photos on two devices (d) the sound on/off setting
21. 21.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
22. 22.💾 What number does this code show?
    let songs = ["Monsoon", "Rain"];
    songs.push("Ocean");
    songs.push("Kites");
    show(songs.length);
23. 23.💾 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
24. 24.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a class leaderboard (d) the sound on/off setting
25. 25.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Sports", "Maths", "Science"];
    show(notes[2]); (a) Science (b) Sports (c) Music (d) Maths
26. 26.💾 What number does this code show?
    let songs = ["Rain", "Kites"];
    songs.push("Ocean");
    show(songs.length);
27. 27.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
28. 28.💾 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
29. 29.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a shared to-do list (d) notes to read offline
30. 30.💾 What number does this code show?
    let points = 6;
    points = points - 4;
    points = points + 5;
    show(points);
31. 31.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon", "Rain", "Sunrise"];
    songs.push("Stars");
    songs.push("Kites");
    show(songs.length);
32. 32.Which of these fits saving in the cloud? (a) notes to read offline (b) a class leaderboard (c) the sound on/off setting (d) your last game level
33. 33.💾 What number does this code show?
    let points = 5;
    points = points - 2;
    points = points + 4;
    show(points);
34. 34.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Sports", "Art"];
    show(notes[2]); (a) Art (b) Maths (c) Sports
36. 36.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
37. 37.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
38. 38.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Kites", "Ocean", "Monsoon", "Sunrise"];
    show(songs[0]); (a) Rain (b) Kites (c) Monsoon (d) Ocean
39. 39.True or false: notes to read offline fits saving on the phone. (a) True (b) False
40. 40.💾 What number does this code show?
    let notes = ["Hindi", "Science", "Sports", "Art"];
    notes.push("Music");
    notes.push("Maths");
    show(notes.length);

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