App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 703 · 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 chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.💾 What number does this code show?
   let points = 9;
   points = points - 8;
   points = points + 1;
   show(points);
3. 3.💾 What number does this code show?
   let lives = 4;
   lives = lives - 1;
   lives = lives + 4;
   show(lives);
4. 4.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the phone is lost (c) you send a message (d) the app is closed
5. 5.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
6. 6.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) a draft you are typing
7. 7.💾 What number does this code show?
   let score = 3;
   score = score - 2;
   score = score + 3;
   show(score);
8. 8.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
9. 9.💾 What number does this code show?
   let score = 5;
   score = score - 5;
   score = score + 4;
   show(score);
10. 10.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 2;
    show(score);
11. 11.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) the sound on/off setting (d) chat messages to friends
12. 12.💾 What number does this code show?
    let points = 6;
    points = points - 4;
    points = points + 4;
    show(points);
13. 13.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 5;
    show(coins);
14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Ocean", "Stars", "Sunrise"];
    show(songs[1]); (a) Sunrise (b) Stars (c) Ocean (d) Kites
15. 15.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) notes to read offline (d) photos on two devices
16. 16.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
17. 17.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
18. 18.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Hindi"];
    show(notes[1]); (a) Science (b) Hindi (c) Art
19. 19.💾 What number does this code show?
    let notes = ["Hindi", "Sports", "Maths", "Science"];
    notes.push("Art");
    show(notes.length);
20. 20.💾 Which works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud backup (d) a cloud leaderboard
21. 21.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) a draft you are typing (d) notes to read offline
22. 22.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
23. 23.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
24. 24.💾 What number does this code show?
    let notes = ["Music", "Hindi"];
    notes.push("Art");
    show(notes.length);
25. 25.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Aman", "Zoya", "Kabir", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Riya (c) Zoya (d) Kabir
26. 26.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
27. 27.💾 What number does this code show?
    let score = 6;
    score = score - 4;
    score = score + 2;
    show(score);
28. 28.True or false: notes to read offline fits saving on the phone. (a) True (b) False
29. 29.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Monsoon", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Monsoon
30. 30.💾 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
31. 31.💾 Which can hold many values in order? (a) a button (b) a list (c) a single number (d) a switch
32. 32.💾 What number does this code show?
    let stars = 7;
    stars = stars - 1;
    stars = stars + 4;
    show(stars);
33. 33.💾 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
34. 34.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 5;
    show(points);
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Zoya", "Kabir", "Meera"];
    show(friends[1]); (a) Riya (b) Kabir (c) Meera (d) Zoya
37. 37.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
38. 38.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 2;
    show(coins);
39. 39.💾 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) Rain (b) Monsoon (c) Sunrise (d) Stars
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Rain", "Monsoon"];
    show(songs[1]); (a) Stars (b) Rain (c) Monsoon

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