App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 676 · 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.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 2 (d) 1
2. 2.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
4. 4.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
5. 5.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
6. 6.💾 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
7. 7.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
8. 8.💾 What number does this code show?
   let songs = ["Ocean", "Sunrise", "Monsoon", "Rain"];
   songs.push("Stars");
   show(songs.length);
9. 9.Which of these fits saving on the phone? (a) a shared to-do list (b) a draft you are typing (c) a class leaderboard (d) chat messages to friends
10. 10.True or false: notes to read offline fits saving on the phone. (a) False (b) True
11. 11.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
12. 12.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
13. 13.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.💾 What number does this code show?
    let points = 5;
    points = points - 2;
    points = points + 1;
    show(points);
15. 15.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) the sound on/off setting (d) chat messages to friends
16. 16.💾 Which works with no internet at all? (a) a shared chat (b) a cloud backup (c) data saved on the phone (d) a cloud leaderboard
17. 17.💾 What number does this code show?
    let notes = ["Sports", "Music"];
    notes.push("Hindi");
    show(notes.length);
18. 18.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Sunrise (c) Monsoon (d) Ocean
19. 19.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Maths", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Hindi (d) Music
20. 20.💾 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
21. 21.💾 What number does this code show?
    let notes = ["Art", "Sports"];
    notes.push("Maths");
    show(notes.length);
22. 22.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting
23. 23.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Stars", "Ocean"];
    show(songs[1]); (a) Sunrise (b) Ocean (c) Stars
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Music", "Maths"];
    show(notes[0]); (a) Music (b) Maths (c) Hindi
25. 25.💾 What number does this code show?
    let friends = ["Kabir", "Meera"];
    friends.push("Arjun");
    friends.push("Aman");
    show(friends.length);
26. 26.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
27. 27.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) never need a password (c) skip the internet (d) shrink the app
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Music"];
    show(notes[0]); (a) Science (b) Music (c) Art
29. 29.💾 What number does this code show?
    let songs = ["Monsoon", "Rain", "Kites"];
    songs.push("Sunrise");
    show(songs.length);
30. 30.💾 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
31. 31.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
32. 32.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Hindi", "Art"];
    show(notes[1]); (a) Art (b) Hindi (c) Science
33. 33.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) a class leaderboard
34. 34.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) chat messages to friends (d) the sound on/off setting
35. 35.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Arjun", "Riya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Arjun (c) Aman (d) Riya
36. 36.💾 What number does this code show?
    let score = 8;
    score = score - 1;
    score = score + 3;
    show(score);
37. 37.💾 What number does this code show?
    let points = 4;
    points = points - 3;
    points = points + 2;
    show(points);
38. 38.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) photos on two devices (d) your last game level
39. 39.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
40. 40.True or false: a class leaderboard fits saving on the phone. (a) True (b) False

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