App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 943 · 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 draft you are typing fits saving in the cloud. (a) True (b) False
2. 2.💾 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
3. 3.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Maths", "Music", "Sports", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Music (c) Science (d) Sports
4. 4.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) notes to read offline (d) a shared to-do list
5. 5.💾 What number does this code show?
   let lives = 5;
   lives = lives - 1;
   lives = lives + 3;
   show(lives);
6. 6.💾 What number does this code show?
   let friends = ["Riya", "Arjun"];
   friends.push("Aman");
   show(friends.length);
7. 7.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a shared to-do list (d) your last game level
8. 8.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) the sound on/off setting (d) photos on two devices
9. 9.Which of these fits saving on the phone? (a) a class leaderboard (b) a draft you are typing (c) photos on two devices (d) a shared to-do list
10. 10.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.💾 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
12. 12.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Sunrise", "Kites"];
    show(songs[0]); (a) Sunrise (b) Kites (c) Ocean
13. 13.💾 What number does this code show?
    let points = 9;
    points = points - 3;
    points = points + 2;
    show(points);
14. 14.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the screen turns off (d) the phone is lost
15. 15.💾 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
16. 16.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Riya", "Meera", "Zoya"];
    show(friends[3]); (a) Aman (b) Riya (c) Meera (d) Kabir
17. 17.💾 What number does this code show?
    let score = 7;
    score = score - 1;
    score = score + 1;
    show(score);
18. 18.💾 What number does this code show?
    let lives = 4;
    lives = lives - 4;
    lives = lives + 3;
    show(lives);
19. 19.💾 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
20. 20.💾 What number does this code show?
    let songs = ["Ocean", "Kites"];
    songs.push("Sunrise");
    show(songs.length);
21. 21.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) a draft you are typing (d) a class leaderboard
22. 22.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Sports", "Music", "Art"];
    show(notes[2]); (a) Sports (b) Art (c) Music (d) Maths
23. 23.💾 What number does this code show?
    let coins = 8;
    coins = coins - 3;
    coins = coins + 4;
    show(coins);
24. 24.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
25. 25.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
26. 26.💾 What number does this code show?
    let points = 4;
    points = points - 2;
    points = points + 1;
    show(points);
27. 27.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
28. 28.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
29. 29.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) notes to read offline (d) chat messages to friends
30. 30.True or false: notes to read offline fits saving on the phone. (a) False (b) True
31. 31.💾 What number does this code show?
    let friends = ["Zoya", "Riya", "Kabir", "Meera"];
    friends.push("Arjun");
    show(friends.length);
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Sunrise", "Kites", "Rain"];
    show(songs[3]); (a) Sunrise (b) Kites (c) Rain (d) Monsoon
33. 33.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Art", "Hindi", "Maths"];
    show(notes[4]); (a) Music (b) Maths (c) Science (d) Art
34. 34.💾 What number does this code show?
    let lives = 7;
    lives = lives - 5;
    lives = lives + 5;
    show(lives);
35. 35.💾 What number does this code show?
    let score = 7;
    score = score - 7;
    score = score + 1;
    show(score);
36. 36.💾 What number does this code show?
    let songs = ["Stars", "Monsoon"];
    songs.push("Sunrise");
    show(songs.length);
37. 37.💾 What number does this code show?
    let notes = ["Sports", "Music", "Hindi", "Maths"];
    notes.push("Science");
    show(notes.length);
38. 38.💾 What number does this code show?
    let notes = ["Music", "Maths", "Sports", "Science"];
    notes.push("Art");
    show(notes.length);
39. 39.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Zoya", "Meera"];
    show(friends[2]); (a) Kabir (b) Zoya (c) Meera
40. 40.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone

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