App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 53 · 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: a draft you are typing fits saving on the phone. (a) False (b) True
2. 2.💾 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
3. 3.💾 What does this code show? (Positions start at 0.)
   let notes = ["Music", "Maths", "Science", "Art"];
   show(notes[1]); (a) Music (b) Science (c) Art (d) Maths
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 photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
6. 6.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) chat messages to friends (d) notes to read offline
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Maths", "Art", "Music"];
   show(notes[2]); (a) Art (b) Maths (c) Music
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.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
10. 10.💾 What number does this code show?
    let friends = ["Aman", "Kabir"];
    friends.push("Riya");
    show(friends.length);
11. 11.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
12. 12.💾 What number does this code show?
    let songs = ["Stars", "Sunrise", "Ocean"];
    songs.push("Rain");
    songs.push("Kites");
    show(songs.length);
13. 13.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) chat messages to friends (d) the sound on/off setting
14. 14.💾 What number does this code show?
    let notes = ["Hindi", "Music", "Art", "Sports"];
    notes.push("Science");
    show(notes.length);
15. 15.💾 What number does this code show?
    let friends = ["Zoya", "Arjun"];
    friends.push("Aman");
    show(friends.length);
16. 16.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 1 (c) 2 (d) 10
17. 17.💾 What number does this code show?
    let coins = 4;
    coins = coins - 1;
    coins = coins + 1;
    show(coins);
18. 18.💾 What number does this code show?
    let notes = ["Art", "Science"];
    notes.push("Hindi");
    show(notes.length);
19. 19.💾 What is a variable? (a) a phone setting (b) a picture (c) a type of screen (d) a named box for a value
20. 20.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) chat messages to friends (d) a class leaderboard
21. 21.💾 Which works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud leaderboard (d) a cloud backup
22. 22.Which of these fits saving on the phone? (a) photos on two devices (b) a draft you are typing (c) a shared to-do list (d) a class leaderboard
23. 23.💾 What number does this code show?
    let coins = 9;
    coins = coins - 9;
    coins = coins + 4;
    show(coins);
24. 24.💾 What number does this code show?
    let coins = 5;
    coins = coins - 5;
    coins = coins + 4;
    show(coins);
25. 25.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) your last game level
26. 26.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
27. 27.💾 What number does this code show?
    let songs = ["Sunrise", "Stars", "Rain", "Kites"];
    songs.push("Monsoon");
    songs.push("Ocean");
    show(songs.length);
28. 28.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Ocean", "Stars", "Monsoon"];
    show(songs[1]); (a) Ocean (b) Stars (c) Kites (d) Monsoon
29. 29.💾 What number does this code show?
    let songs = ["Monsoon", "Kites"];
    songs.push("Rain");
    show(songs.length);
30. 30.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
31. 31.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
32. 32.True or false: photos on two devices fits saving on the phone. (a) True (b) False
33. 33.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Sports", "Music", "Science"];
    show(notes[3]); (a) Sports (b) Science (c) Music (d) Maths
34. 34.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Monsoon", "Kites", "Rain"];
    show(songs[2]); (a) Monsoon (b) Rain (c) Ocean (d) Kites
35. 35.💾 What number does this code show?
    let friends = ["Meera", "Kabir", "Zoya"];
    friends.push("Riya");
    show(friends.length);
36. 36.💾 What number does this code show?
    let friends = ["Riya", "Zoya", "Aman", "Meera"];
    friends.push("Arjun");
    show(friends.length);
37. 37.💾 What number does this code show?
    let songs = ["Rain", "Kites", "Stars"];
    songs.push("Monsoon");
    show(songs.length);
38. 38.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Music", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Sports (c) Art (d) Music
39. 39.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
40. 40.💾 What number does this code show?
    let lives = 7;
    lives = lives - 4;
    lives = lives + 1;
    show(lives);

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