App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 218 · 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: the sound on/off setting fits saving in the cloud. (a) True (b) False
2. 2.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) notes to read offline (d) a shared to-do list
3. 3.💾 What number does this code show?
   let friends = ["Riya", "Kabir"];
   friends.push("Aman");
   show(friends.length);
4. 4.💾 pop() takes off the last item. What does this code show?
   let friends = ["Kabir", "Arjun", "Meera", "Zoya", "Riya"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Arjun (b) Meera (c) Zoya (d) Kabir
5. 5.💾 Which can hold many values in order? (a) a button (b) a single number (c) a switch (d) a list
6. 6.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the phone is lost (d) the screen turns off
8. 8.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) your last game level (d) a class leaderboard
9. 9.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Maths", "Hindi", "Science", "Music"];
   show(notes[4]); (a) Music (b) Art (c) Maths (d) Hindi
10. 10.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Maths", "Science", "Hindi"];
    show(notes[0]); (a) Hindi (b) Science (c) Art (d) Maths
11. 11.💾 What number does this code show?
    let score = 8;
    score = score - 6;
    score = score + 5;
    show(score);
12. 12.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Science"];
    show(notes[0]); (a) Art (b) Science (c) Sports
13. 13.💾 What number does this code show?
    let notes = ["Art", "Music", "Maths"];
    notes.push("Hindi");
    notes.push("Sports");
    show(notes.length);
14. 14.💾 What number does this code show?
    let notes = ["Art", "Maths", "Hindi", "Music"];
    notes.push("Sports");
    show(notes.length);
15. 15.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Rain", "Monsoon", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Stars (c) Sunrise (d) Rain
16. 16.💾 What number does this code show?
    let songs = ["Monsoon", "Kites"];
    songs.push("Stars");
    songs.push("Ocean");
    show(songs.length);
17. 17.💾 What number does this code show?
    let lives = 5;
    lives = lives - 1;
    lives = lives + 4;
    show(lives);
18. 18.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Music", "Hindi"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
19. 19.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
20. 20.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting
21. 21.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Stars", "Monsoon"];
    show(songs[2]); (a) Monsoon (b) Stars (c) Ocean
22. 22.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 5;
    show(coins);
23. 23.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
24. 24.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
25. 25.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) chat messages to friends (d) notes to read offline
26. 26.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
27. 27.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) data saved on the phone (d) a shared chat
28. 28.💾 What number does this code show?
    let notes = ["Art", "Music", "Sports", "Hindi"];
    notes.push("Maths");
    show(notes.length);
29. 29.Which of these fits saving in the cloud? (a) photos on two devices (b) notes to read offline (c) your last game level (d) a draft you are typing
30. 30.💾 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
31. 31.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Meera", "Riya", "Zoya"];
    show(friends[3]); (a) Aman (b) Meera (c) Riya (d) Kabir
32. 32.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Art", "Maths"];
    show(notes[0]); (a) Maths (b) Art (c) Music
33. 33.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
34. 34.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) the sound on/off setting
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Hindi", "Music", "Maths"];
    show(notes[1]); (a) Art (b) Hindi (c) Music (d) Maths
36. 36.💾 What number does this code show?
    let lives = 6;
    lives = lives - 6;
    lives = lives + 1;
    show(lives);
37. 37.💾 What number does this code show?
    let notes = ["Music", "Sports"];
    notes.push("Hindi");
    show(notes.length);
38. 38.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
39. 39.💾 What number does this code show?
    let lives = 7;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
40. 40.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True

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