App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 482 · 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.💾 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
2. 2.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) chat messages to friends (d) your last game level
3. 3.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the phone is lost (c) the screen turns off (d) the app is closed
5. 5.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
6. 6.💾 What number does this code show?
   let stars = 9;
   stars = stars - 6;
   stars = stars + 1;
   show(stars);
7. 7.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
8. 8.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Music", "Science", "Maths"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Science (c) Art (d) Music
10. 10.💾 What is a variable? (a) a picture (b) a type of screen (c) a phone setting (d) a named box for a value
11. 11.💾 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
12. 12.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
13. 13.True or false: your last game level fits saving on the phone. (a) True (b) False
14. 14.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) notes to read offline (d) chat messages to friends
15. 15.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
16. 16.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
17. 17.💾 What number does this code show?
    let notes = ["Music", "Maths"];
    notes.push("Hindi");
    show(notes.length);
18. 18.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) data saved on the phone (d) a cloud leaderboard
19. 19.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
20. 20.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Stars", "Ocean", "Rain"];
    show(songs[3]); (a) Monsoon (b) Stars (c) Rain (d) Ocean
21. 21.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Ocean", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Monsoon (c) Ocean
22. 22.💾 What number does this code show?
    let notes = ["Music", "Science", "Hindi", "Sports"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
23. 23.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) the sound on/off setting (d) a class leaderboard
24. 24.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) a class leaderboard (d) the sound on/off setting
25. 25.Which of these fits saving in the cloud? (a) a draft you are typing (b) chat messages to friends (c) the sound on/off setting (d) notes to read offline
26. 26.💾 What number does this code show?
    let score = 5;
    score = score - 4;
    score = score + 2;
    show(score);
27. 27.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
28. 28.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a draft you are typing (d) a shared to-do list
29. 29.💾 What number does this code show?
    let points = 4;
    points = points - 3;
    points = points + 1;
    show(points);
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Monsoon", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Sunrise (c) Rain (d) Kites
31. 31.💾 What number does this code show?
    let songs = ["Stars", "Kites", "Sunrise"];
    songs.push("Ocean");
    songs.push("Monsoon");
    show(songs.length);
32. 32.💾 Which can hold many values in order? (a) a button (b) a single number (c) a switch (d) a list
33. 33.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
34. 34.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
35. 35.💾 What number does this code show?
    let friends = ["Zoya", "Kabir", "Meera"];
    friends.push("Riya");
    friends.push("Aman");
    show(friends.length);
36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Music
37. 37.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 0 (c) 2 (d) 10
38. 38.💾 What number does this code show?
    let lives = 6;
    lives = lives - 4;
    lives = lives + 3;
    show(lives);
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Monsoon", "Rain", "Ocean"];
    show(songs[4]); (a) Sunrise (b) Ocean (c) Monsoon (d) Kites
40. 40.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 5;
    show(score);

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