App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 328 · 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: chat messages to friends fits saving in the cloud. (a) True (b) False
2. 2.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Art", "Music", "Maths", "Hindi"];
   show(notes[0]); (a) Sports (b) Maths (c) Art (d) Music
4. 4.Which of these fits saving on the phone? (a) chat messages to friends (b) notes to read offline (c) a shared to-do list (d) a class leaderboard
5. 5.💾 pop() takes off the last item. What does this code show?
   let notes = ["Music", "Art", "Science", "Sports", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Art (c) Music (d) Science
6. 6.💾 What number does this code show?
   let stars = 6;
   stars = stars - 3;
   stars = stars + 4;
   show(stars);
7. 7.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
8. 8.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
9. 9.💾 What number does this code show?
   let songs = ["Kites", "Stars"];
   songs.push("Ocean");
   songs.push("Sunrise");
   show(songs.length);
10. 10.💾 What number does this code show?
    let notes = ["Music", "Maths"];
    notes.push("Science");
    notes.push("Hindi");
    show(notes.length);
11. 11.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean"];
    songs.push("Stars");
    show(songs.length);
12. 12.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Hindi", "Art"];
    show(notes[0]); (a) Art (b) Science (c) Hindi
13. 13.True or false: photos on two devices fits saving on the phone. (a) False (b) True
14. 14.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
15. 15.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon", "Kites"];
    songs.push("Rain");
    show(songs.length);
16. 16.💾 What is a variable? (a) a picture (b) a phone setting (c) a named box for a value (d) a type of screen
17. 17.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Rain", "Monsoon", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Ocean (c) Sunrise (d) Monsoon
18. 18.💾 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
19. 19.💾 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
20. 20.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
21. 21.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
22. 22.True or false: notes to read offline fits saving on the phone. (a) True (b) False
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Hindi", "Art", "Music"];
    show(notes[3]); (a) Maths (b) Art (c) Hindi (d) Music
24. 24.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) notes to read offline (d) chat messages to friends
25. 25.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) the sound on/off setting (d) photos on two devices
26. 26.True or false: your last game level fits saving in the cloud. (a) True (b) False
27. 27.💾 What number does this code show?
    let songs = ["Kites", "Rain"];
    songs.push("Ocean");
    songs.push("Stars");
    show(songs.length);
28. 28.💾 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
29. 29.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
30. 30.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
31. 31.💾 What number does this code show?
    let friends = ["Riya", "Zoya"];
    friends.push("Meera");
    show(friends.length);
32. 32.💾 What number does this code show?
    let notes = ["Science", "Maths", "Art", "Hindi"];
    notes.push("Music");
    show(notes.length);
33. 33.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
34. 34.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) your last game level (d) photos on two devices
35. 35.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the screen turns off (d) the phone is lost
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Monsoon", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Sunrise (c) Monsoon
37. 37.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
38. 38.💾 What number does this code show?
    let notes = ["Maths", "Science"];
    notes.push("Hindi");
    show(notes.length);
39. 39.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
40. 40.💾 What number does this code show?
    let points = 5;
    points = points - 3;
    points = points + 5;
    show(points);

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