App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 833 · 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.💾 What number does this code show?
   let notes = ["Sports", "Science", "Maths"];
   notes.push("Art");
   notes.push("Hindi");
   show(notes.length);
2. 2.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Art", "Science", "Music", "Hindi"];
   show(notes[2]); (a) Music (b) Sports (c) Science (d) Art
3. 3.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) a cloud backup (d) data saved on the phone
4. 4.💾 What does this code show? (Positions start at 0.)
   let friends = ["Aman", "Meera", "Kabir"];
   show(friends[0]); (a) Aman (b) Meera (c) Kabir
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.Which of these fits saving on the phone? (a) a shared to-do list (b) a draft you are typing (c) a class leaderboard (d) chat messages to friends
7. 7.💾 What number does this code show?
   let score = 4;
   score = score - 1;
   score = score + 5;
   show(score);
8. 8.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a shared to-do list (d) notes to read offline
9. 9.💾 pop() takes off the last item. What does this code show?
   let notes = ["Maths", "Art", "Music", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Maths (c) Hindi (d) Music
10. 10.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Sports", "Music", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Music (d) Art
11. 11.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 2 (d) 1
12. 12.💾 What number does this code show?
    let notes = ["Science", "Maths", "Art", "Hindi"];
    notes.push("Sports");
    notes.push("Music");
    show(notes.length);
13. 13.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) you send a message (c) the screen turns off (d) the app is closed
14. 14.True or false: your last game level fits saving on the phone. (a) False (b) True
15. 15.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
16. 16.💾 What number does this code show?
    let lives = 6;
    lives = lives - 3;
    lives = lives + 1;
    show(lives);
17. 17.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Sunrise", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Sunrise (c) Monsoon
18. 18.💾 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
19. 19.💾 What number does this code show?
    let stars = 4;
    stars = stars - 4;
    stars = stars + 5;
    show(stars);
20. 20.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
21. 21.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Sports", "Art"];
    show(notes[1]); (a) Maths (b) Art (c) Sports
22. 22.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
23. 23.💾 What number does this code show?
    let score = 5;
    score = score - 5;
    score = score + 4;
    show(score);
24. 24.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 2;
    show(coins);
25. 25.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
26. 26.True or false: your last game level fits saving in the cloud. (a) False (b) True
27. 27.💾 What number does this code show?
    let notes = ["Science", "Music", "Sports", "Maths"];
    notes.push("Art");
    show(notes.length);
28. 28.💾 What number does this code show?
    let score = 5;
    score = score - 2;
    score = score + 2;
    show(score);
29. 29.💾 What number does this code show?
    let score = 9;
    score = score - 8;
    score = score + 4;
    show(score);
30. 30.💾 What number does this code show?
    let songs = ["Stars", "Ocean", "Rain"];
    songs.push("Sunrise");
    songs.push("Kites");
    show(songs.length);
31. 31.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
32. 32.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) the sound on/off setting (d) a class leaderboard
33. 33.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
34. 34.💾 What number does this code show?
    let friends = ["Meera", "Riya", "Zoya", "Aman"];
    friends.push("Kabir");
    show(friends.length);
35. 35.💾 What number does this code show?
    let score = 8;
    score = score - 1;
    score = score + 4;
    show(score);
36. 36.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a class leaderboard (c) a draft you are typing (d) notes to read offline
37. 37.💾 What is a variable? (a) a picture (b) a named box for a value (c) a type of screen (d) a phone setting
38. 38.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) a draft you are typing (d) a shared to-do list
39. 39.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Riya"];
    show(friends[2]); (a) Aman (b) Kabir (c) Riya
40. 40.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) chat messages to friends (d) notes to read offline

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