App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 211 · 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 class leaderboard fits saving on the phone. (a) False (b) True
2. 2.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.💾 What number does this code show?
   let friends = ["Kabir", "Riya", "Zoya"];
   friends.push("Aman");
   friends.push("Arjun");
   show(friends.length);
4. 4.💾 What number does this code show?
   let songs = ["Rain", "Sunrise"];
   songs.push("Stars");
   show(songs.length);
5. 5.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
6. 6.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Art", "Maths"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Science (b) Art (c) Maths
8. 8.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 0 (d) 10
9. 9.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
10. 10.💾 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
11. 11.True or false: your last game level fits saving in the cloud. (a) True (b) False
12. 12.True or false: notes to read offline fits saving on the phone. (a) False (b) True
13. 13.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the phone is lost (d) the app is closed
14. 14.💾 Which can hold many values in order? (a) a button (b) a single number (c) a list (d) a switch
15. 15.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Stars", "Rain", "Ocean", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Monsoon (c) Stars (d) Rain
16. 16.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Kabir", "Arjun"];
    show(friends[0]); (a) Meera (b) Arjun (c) Kabir
17. 17.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
18. 18.💾 What is a variable? (a) a named box for a value (b) a type of screen (c) a picture (d) a phone setting
19. 19.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Meera", "Aman", "Arjun", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Meera (c) Aman (d) Arjun
20. 20.💾 What number does this code show?
    let points = 6;
    points = points - 5;
    points = points + 1;
    show(points);
21. 21.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
22. 22.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
23. 23.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
24. 24.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) a draft you are typing
25. 25.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
26. 26.💾 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
27. 27.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) the sound on/off setting (d) a class leaderboard
28. 28.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise"];
    songs.push("Ocean");
    show(songs.length);
29. 29.💾 Which works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud backup (d) a cloud leaderboard
30. 30.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Music", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Hindi (d) Art
31. 31.💾 What number does this code show?
    let coins = 9;
    coins = coins - 9;
    coins = coins + 5;
    show(coins);
32. 32.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Aman", "Kabir", "Riya", "Zoya"];
    show(friends[1]); (a) Meera (b) Kabir (c) Riya (d) Aman
33. 33.Which of these fits saving in the cloud? (a) the sound on/off setting (b) photos on two devices (c) notes to read offline (d) your last game level
34. 34.💾 What number does this code show?
    let coins = 5;
    coins = coins - 1;
    coins = coins + 4;
    show(coins);
35. 35.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Monsoon", "Kites", "Stars", "Sunrise"];
    show(songs[4]); (a) Kites (b) Sunrise (c) Monsoon (d) Ocean
36. 36.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
37. 37.Which of these fits saving in the cloud? (a) a class leaderboard (b) a draft you are typing (c) the sound on/off setting (d) your last game level
38. 38.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Kabir", "Zoya", "Aman"];
    show(friends[2]); (a) Kabir (b) Zoya (c) Aman (d) Arjun
39. 39.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
40. 40.💾 What number does this code show?
    let notes = ["Music", "Science"];
    notes.push("Art");
    show(notes.length);

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