App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 335 · 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 can hold many values in order? (a) a single number (b) a button (c) a list (d) a switch
2. 2.True or false: photos on two devices fits saving on the phone. (a) True (b) False
3. 3.💾 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
4. 4.💾 What number does this code show?
   let notes = ["Sports", "Science", "Maths", "Music"];
   notes.push("Art");
   notes.push("Hindi");
   show(notes.length);
5. 5.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) never need a password (c) skip the internet (d) use it on any device
6. 6.💾 pop() takes off the last item. What does this code show?
   let songs = ["Rain", "Sunrise", "Kites"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Sunrise
7. 7.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) chat messages to friends (d) the sound on/off setting
8. 8.💾 What number does this code show?
   let score = 3;
   score = score - 1;
   score = score + 4;
   show(score);
9. 9.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) data saved on the phone (d) a shared chat
10. 10.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
11. 11.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the phone is lost (d) the screen turns off
12. 12.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) photos on two devices (d) notes to read offline
13. 13.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) chat messages to friends (d) your last game level
14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Stars", "Ocean", "Monsoon", "Sunrise"];
    show(songs[3]); (a) Ocean (b) Rain (c) Monsoon (d) Stars
15. 15.💾 What number does this code show?
    let coins = 4;
    coins = coins - 2;
    coins = coins + 2;
    show(coins);
16. 16.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
17. 17.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
18. 18.💾 What number does this code show?
    let coins = 6;
    coins = coins - 5;
    coins = coins + 1;
    show(coins);
19. 19.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.💾 What is a variable? (a) a phone setting (b) a picture (c) a type of screen (d) a named box for a value
21. 21.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Arjun", "Aman"];
    show(friends[2]); (a) Arjun (b) Aman (c) Zoya
22. 22.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
23. 23.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
24. 24.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
25. 25.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise", "Kites"];
    songs.push("Rain");
    show(songs.length);
26. 26.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) chat messages to friends
27. 27.💾 What number does this code show?
    let notes = ["Science", "Hindi", "Music", "Sports"];
    notes.push("Maths");
    show(notes.length);
28. 28.Which of these fits saving on the phone? (a) a draft you are typing (b) a shared to-do list (c) chat messages to friends (d) photos on two devices
29. 29.💾 What number does this code show?
    let notes = ["Music", "Hindi", "Maths"];
    notes.push("Science");
    show(notes.length);
30. 30.💾 What number does this code show?
    let coins = 5;
    coins = coins - 3;
    coins = coins + 1;
    show(coins);
31. 31.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
32. 32.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Science", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Sports (c) Science
33. 33.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Maths", "Science", "Art"];
    show(notes[0]); (a) Maths (b) Art (c) Sports (d) Science
34. 34.💾 What number does this code show?
    let coins = 9;
    coins = coins - 1;
    coins = coins + 1;
    show(coins);
35. 35.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) notes to read offline (d) a class leaderboard
36. 36.Which of these fits saving in the cloud? (a) notes to read offline (b) a shared to-do list (c) your last game level (d) a draft you are typing
37. 37.💾 What number does this code show?
    let stars = 4;
    stars = stars - 4;
    stars = stars + 2;
    show(stars);
38. 38.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Kites", "Sunrise", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Kites (c) Sunrise (d) Stars
39. 39.💾 What number does this code show?
    let coins = 5;
    coins = coins - 3;
    coins = coins + 4;
    show(coins);
40. 40.True or false: a class leaderboard fits saving on the phone. (a) False (b) True

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