App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 793 · 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: chat messages to friends fits saving on the phone. (a) True (b) False
2. 2.💾 pop() takes off the last item. What does this code show?
   let songs = ["Monsoon", "Ocean", "Rain", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Ocean (b) Stars (c) Rain (d) Monsoon
3. 3.💾 What number does this code show?
   let friends = ["Aman", "Meera", "Kabir", "Riya"];
   friends.push("Arjun");
   show(friends.length);
4. 4.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
5. 5.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
6. 6.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a named box for a value (d) a picture
7. 7.True or false: photos on two devices fits saving on the phone. (a) False (b) True
8. 8.💾 What number does this code show?
   let coins = 6;
   coins = coins - 2;
   coins = coins + 2;
   show(coins);
9. 9.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
10. 10.💾 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
11. 11.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
12. 12.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
13. 13.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
14. 14.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
15. 15.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
16. 16.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
17. 17.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a draft you are typing (d) a shared to-do list
18. 18.💾 What number does this code show?
    let friends = ["Meera", "Aman"];
    friends.push("Zoya");
    friends.push("Kabir");
    show(friends.length);
19. 19.💾 What number does this code show?
    let stars = 4;
    stars = stars - 1;
    stars = stars + 3;
    show(stars);
20. 20.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) photos on two devices (d) the sound on/off setting
21. 21.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
22. 22.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) your last game level (d) a shared to-do list
23. 23.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a cloud backup (c) a shared chat (d) data saved on the phone
24. 24.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Kites"];
    show(songs[2]); (a) Rain (b) Sunrise (c) Kites
25. 25.💾 What number does this code show?
    let notes = ["Art", "Music"];
    notes.push("Maths");
    notes.push("Science");
    show(notes.length);
26. 26.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 2;
    show(lives);
27. 27.💾 What number does this code show?
    let friends = ["Aman", "Riya"];
    friends.push("Meera");
    friends.push("Arjun");
    show(friends.length);
28. 28.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
29. 29.True or false: your last game level fits saving on the phone. (a) True (b) False
30. 30.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
31. 31.💾 What number does this code show?
    let notes = ["Science", "Art", "Sports", "Maths"];
    notes.push("Hindi");
    notes.push("Music");
    show(notes.length);
32. 32.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Science", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Sports (c) Art
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.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the phone is lost (c) the app is closed (d) the screen turns off
35. 35.💾 What number does this code show?
    let notes = ["Hindi", "Art", "Maths"];
    notes.push("Science");
    show(notes.length);
36. 36.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
37. 37.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) a shared to-do list (d) notes to read offline
38. 38.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
39. 39.💾 What number does this code show?
    let score = 9;
    score = score - 8;
    score = score + 4;
    show(score);
40. 40.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) the sound on/off setting (d) a shared to-do list

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