App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 960 · 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 on the phone? (a) a class leaderboard (b) chat messages to friends (c) a draft you are typing (d) a shared to-do list
2. 2.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) data saved on the phone (d) a cloud leaderboard
3. 3.💾 pop() takes off the last item. What does this code show?
   let notes = ["Music", "Art", "Maths"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Art (c) Music
4. 4.💾 What does this code show? (Positions start at 0.)
   let notes = ["Maths", "Sports", "Art"];
   show(notes[0]); (a) Art (b) Maths (c) Sports
5. 5.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) chat messages to friends (d) photos on two devices
6. 6.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) photos on two devices (d) a draft you are typing
7. 7.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
8. 8.💾 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
9. 9.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a picture (d) a named box for a value
10. 10.💾 What number does this code show?
    let notes = ["Sports", "Maths"];
    notes.push("Hindi");
    show(notes.length);
11. 11.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
12. 12.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
13. 13.💾 What number does this code show?
    let points = 7;
    points = points - 3;
    points = points + 2;
    show(points);
14. 14.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Ocean", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Ocean (c) Kites
15. 15.Which of these fits saving on the phone? (a) the sound on/off setting (b) a shared to-do list (c) photos on two devices (d) chat messages to friends
16. 16.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Kites", "Stars"];
    show(songs[2]); (a) Kites (b) Stars (c) Monsoon (d) Rain
17. 17.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Music", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Maths (d) Science
18. 18.Which of these fits saving in the cloud? (a) a class leaderboard (b) a draft you are typing (c) notes to read offline (d) your last game level
19. 19.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.💾 What number does this code show?
    let notes = ["Sports", "Hindi", "Maths"];
    notes.push("Science");
    notes.push("Music");
    show(notes.length);
21. 21.💾 What number does this code show?
    let friends = ["Meera", "Riya"];
    friends.push("Zoya");
    show(friends.length);
22. 22.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) use it on any device (c) shrink the app (d) never need a password
23. 23.💾 What number does this code show?
    let friends = ["Zoya", "Riya", "Arjun"];
    friends.push("Meera");
    friends.push("Kabir");
    show(friends.length);
24. 24.💾 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
25. 25.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
26. 26.💾 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
27. 27.💾 What number does this code show?
    let notes = ["Art", "Maths", "Music"];
    notes.push("Sports");
    show(notes.length);
28. 28.True or false: your last game level fits saving on the phone. (a) False (b) True
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Music", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Sports (c) Music (d) Hindi
30. 30.💾 What number does this code show?
    let friends = ["Kabir", "Meera"];
    friends.push("Arjun");
    show(friends.length);
31. 31.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Art", "Sports", "Science", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Science (d) Art
32. 32.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
33. 33.💾 Which can hold many values in order? (a) a list (b) a button (c) a switch (d) a single number
34. 34.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
35. 35.💾 What number does this code show?
    let friends = ["Meera", "Aman", "Riya", "Kabir"];
    friends.push("Zoya");
    friends.push("Arjun");
    show(friends.length);
36. 36.True or false: notes to read offline fits saving on the phone. (a) True (b) False
37. 37.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) chat messages to friends (d) notes to read offline
38. 38.💾 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
39. 39.💾 What number does this code show?
    let points = 6;
    points = points - 1;
    points = points + 3;
    show(points);
40. 40.True or false: a class leaderboard fits saving on the phone. (a) False (b) True

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