App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 759 · 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.💾 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
2. 2.💾 pop() takes off the last item. What does this code show?
   let songs = ["Rain", "Sunrise", "Monsoon", "Kites", "Ocean"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Sunrise (c) Rain (d) Monsoon
3. 3.💾 What number does this code show?
   let notes = ["Music", "Sports", "Maths"];
   notes.push("Hindi");
   show(notes.length);
4. 4.💾 What number does this code show?
   let stars = 7;
   stars = stars - 1;
   stars = stars + 5;
   show(stars);
5. 5.💾 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
6. 6.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a shared to-do list (d) a draft you are typing
7. 7.💾 What number does this code show?
   let stars = 4;
   stars = stars - 2;
   stars = stars + 4;
   show(stars);
8. 8.💾 What number does this code show?
   let lives = 3;
   lives = lives - 1;
   lives = lives + 2;
   show(lives);
9. 9.💾 What number does this code show?
   let friends = ["Riya", "Meera"];
   friends.push("Arjun");
   show(friends.length);
10. 10.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
11. 11.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
12. 12.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
13. 13.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 0 (d) 1
14. 14.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the app is closed (c) you send a message (d) the phone is lost
15. 15.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
16. 16.💾 What number does this code show?
    let lives = 7;
    lives = lives - 6;
    lives = lives + 5;
    show(lives);
17. 17.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
18. 18.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
19. 19.💾 What number does this code show?
    let songs = ["Kites", "Monsoon"];
    songs.push("Ocean");
    show(songs.length);
20. 20.💾 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
21. 21.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
22. 22.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Kites"];
    songs.push("Monsoon");
    show(songs.length);
23. 23.💾 What number does this code show?
    let songs = ["Monsoon", "Kites", "Stars"];
    songs.push("Rain");
    show(songs.length);
24. 24.💾 What number does this code show?
    let friends = ["Aman", "Zoya"];
    friends.push("Riya");
    show(friends.length);
25. 25.💾 What number does this code show?
    let friends = ["Riya", "Aman"];
    friends.push("Zoya");
    friends.push("Meera");
    show(friends.length);
26. 26.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) the sound on/off setting (d) a shared to-do list
27. 27.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a picture (d) a type of screen
28. 28.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
29. 29.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) your last game level (d) photos on two devices
30. 30.True or false: your last game level fits saving in the cloud. (a) True (b) False
31. 31.True or false: photos on two devices fits saving on the phone. (a) True (b) False
32. 32.💾 What number does this code show?
    let songs = ["Monsoon", "Ocean"];
    songs.push("Kites");
    show(songs.length);
33. 33.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) never need a password (c) shrink the app (d) skip the internet
34. 34.💾 What number does this code show?
    let notes = ["Science", "Sports", "Art", "Music"];
    notes.push("Hindi");
    show(notes.length);
35. 35.Which of these fits saving in the cloud? (a) your last game level (b) chat messages to friends (c) the sound on/off setting (d) notes to read offline
36. 36.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
37. 37.💾 Which works with no internet at all? (a) a shared chat (b) a cloud leaderboard (c) a cloud backup (d) data saved on the phone
38. 38.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
39. 39.💾 What number does this code show?
    let notes = ["Science", "Maths", "Hindi", "Sports"];
    notes.push("Art");
    notes.push("Music");
    show(notes.length);
40. 40.💾 What number does this code show?
    let friends = ["Meera", "Aman", "Riya"];
    friends.push("Kabir");
    friends.push("Arjun");
    show(friends.length);

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