App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 406 · 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.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) a shared to-do list (d) the sound on/off setting
2. 2.💾 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
3. 3.Which of these fits saving on the phone? (a) chat messages to friends (b) your last game level (c) a shared to-do list (d) photos on two devices
4. 4.Which of these fits saving in the cloud? (a) notes to read offline (b) chat messages to friends (c) your last game level (d) the sound on/off setting
5. 5.💾 What does this code show? (Positions start at 0.)
   let notes = ["Maths", "Art", "Music", "Hindi", "Sports"];
   show(notes[4]); (a) Music (b) Sports (c) Maths (d) Art
6. 6.💾 Which works with no internet at all? (a) a shared chat (b) a cloud backup (c) a cloud leaderboard (d) data saved on the phone
7. 7.True or false: notes to read offline fits saving on the phone. (a) False (b) True
8. 8.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
9. 9.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Rain", "Stars"];
    show(songs[0]); (a) Sunrise (b) Stars (c) Kites (d) Rain
11. 11.💾 What number does this code show?
    let notes = ["Music", "Science"];
    notes.push("Art");
    show(notes.length);
12. 12.💾 What number does this code show?
    let songs = ["Rain", "Stars", "Kites"];
    songs.push("Ocean");
    songs.push("Sunrise");
    show(songs.length);
13. 13.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Zoya", "Riya"];
    show(friends[2]); (a) Riya (b) Zoya (c) Meera
14. 14.💾 What is a variable? (a) a type of screen (b) a picture (c) a phone setting (d) a named box for a value
15. 15.Which of these fits saving on the phone? (a) photos on two devices (b) a draft you are typing (c) a class leaderboard (d) chat messages to friends
16. 16.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 10 (c) 2 (d) 0
17. 17.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
18. 18.💾 What number does this code show?
    let points = 9;
    points = points - 7;
    points = points + 1;
    show(points);
19. 19.💾 Which can hold many values in order? (a) a button (b) a single number (c) a list (d) a switch
20. 20.💾 What number does this code show?
    let friends = ["Aman", "Arjun"];
    friends.push("Meera");
    friends.push("Zoya");
    show(friends.length);
21. 21.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
22. 22.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Riya", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Riya (c) Meera
23. 23.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Meera", "Aman"];
    show(friends[0]); (a) Meera (b) Arjun (c) Aman
24. 24.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
25. 25.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) never need a password (c) skip the internet (d) shrink the app
26. 26.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Ocean", "Rain"];
    show(songs[2]); (a) Ocean (b) Rain (c) Sunrise
27. 27.💾 What number does this code show?
    let friends = ["Aman", "Zoya"];
    friends.push("Arjun");
    show(friends.length);
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Music", "Science", "Art", "Sports"];
    show(notes[2]); (a) Music (b) Science (c) Art (d) Maths
29. 29.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
30. 30.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
31. 31.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean", "Stars", "Monsoon"];
    songs.push("Kites");
    songs.push("Rain");
    show(songs.length);
32. 32.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Ocean", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Monsoon (c) Ocean
33. 33.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) your last game level (d) a class leaderboard
34. 34.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Kabir", "Zoya"];
    show(friends[2]); (a) Zoya (b) Meera (c) Aman (d) Kabir
36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Art", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Sports (c) Maths
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Hindi", "Maths", "Art", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Sports (c) Hindi (d) Maths
38. 38.💾 What number does this code show?
    let songs = ["Kites", "Stars"];
    songs.push("Ocean");
    show(songs.length);
39. 39.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Sunrise", "Ocean", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Sunrise (d) Ocean
40. 40.💾 What number does this code show?
    let lives = 3;
    lives = lives - 2;
    lives = lives + 1;
    show(lives);

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