App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 121 · 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: your last game level fits saving in the cloud. (a) True (b) False
2. 2.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
3. 3.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) chat messages to friends
4. 4.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
5. 5.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
6. 6.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.💾 What number does this code show?
   let notes = ["Music", "Hindi", "Sports"];
   notes.push("Science");
   show(notes.length);
8. 8.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
9. 9.True or false: your last game level fits saving on the phone. (a) True (b) False
10. 10.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Riya", "Kabir", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Kabir (c) Meera (d) Zoya
11. 11.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
12. 12.💾 What number does this code show?
    let songs = ["Stars", "Ocean"];
    songs.push("Kites");
    show(songs.length);
13. 13.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
14. 14.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Monsoon", "Sunrise", "Ocean", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Ocean (c) Sunrise (d) Stars
15. 15.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Zoya (c) Riya
16. 16.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Sunrise", "Ocean", "Monsoon"];
    show(songs[4]); (a) Rain (b) Kites (c) Monsoon (d) Sunrise
17. 17.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
18. 18.💾 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
19. 19.💾 What number does this code show?
    let notes = ["Music", "Science"];
    notes.push("Sports");
    notes.push("Hindi");
    show(notes.length);
20. 20.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
21. 21.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Science
22. 22.💾 Which can hold many values in order? (a) a button (b) a list (c) a switch (d) a single number
23. 23.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) chat messages to friends
24. 24.💾 What number does this code show?
    let friends = ["Zoya", "Kabir", "Arjun"];
    friends.push("Meera");
    show(friends.length);
25. 25.💾 What number does this code show?
    let points = 4;
    points = points - 4;
    points = points + 5;
    show(points);
26. 26.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Sports", "Music", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Art (c) Maths (d) Music
27. 27.💾 What number does this code show?
    let notes = ["Music", "Sports", "Science"];
    notes.push("Hindi");
    show(notes.length);
28. 28.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Hindi", "Maths"];
    show(notes[0]); (a) Music (b) Sports (c) Hindi (d) Maths
30. 30.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) use it on any device (d) skip the internet
31. 31.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Zoya", "Aman", "Meera"];
    show(friends[2]); (a) Aman (b) Meera (c) Arjun (d) Zoya
32. 32.💾 What is a variable? (a) a named box for a value (b) a picture (c) a phone setting (d) a type of screen
33. 33.💾 What number does this code show?
    let notes = ["Music", "Hindi", "Art", "Maths"];
    notes.push("Science");
    show(notes.length);
34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Ocean", "Rain", "Stars", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Monsoon (d) Stars
35. 35.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
36. 36.💾 What number does this code show?
    let lives = 7;
    lives = lives - 4;
    lives = lives + 1;
    show(lives);
37. 37.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Stars", "Ocean", "Rain", "Kites"];
    show(songs[2]); (a) Sunrise (b) Rain (c) Stars (d) Ocean
38. 38.💾 What number does this code show?
    let songs = ["Kites", "Monsoon", "Sunrise", "Ocean"];
    songs.push("Rain");
    songs.push("Stars");
    show(songs.length);
39. 39.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) notes to read offline (d) a class leaderboard
40. 40.True or false: photos on two devices fits saving on the phone. (a) False (b) True

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