App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 879 · 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: notes to read offline fits saving in the cloud. (a) True (b) False
2. 2.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the phone is lost (c) the app is closed (d) you send a message
3. 3.💾 What number does this code show?
   let stars = 5;
   stars = stars - 1;
   stars = stars + 5;
   show(stars);
4. 4.💾 What number does this code show?
   let songs = ["Ocean", "Monsoon"];
   songs.push("Kites");
   show(songs.length);
5. 5.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
6. 6.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Sports", "Music"];
   show(notes[2]); (a) Sports (b) Art (c) Music
7. 7.💾 What does this code show? (Positions start at 0.)
   let songs = ["Sunrise", "Kites", "Stars", "Ocean", "Rain"];
   show(songs[3]); (a) Kites (b) Sunrise (c) Ocean (d) Stars
8. 8.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) photos on two devices
9. 9.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) use it on any device (d) shrink the app
10. 10.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.💾 What is a variable? (a) a phone setting (b) a picture (c) a type of screen (d) a named box for a value
12. 12.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Stars (c) Monsoon
13. 13.💾 What number does this code show?
    let songs = ["Kites", "Rain"];
    songs.push("Ocean");
    songs.push("Monsoon");
    show(songs.length);
14. 14.💾 Which can hold many values in order? (a) a single number (b) a button (c) a list (d) a switch
15. 15.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) notes to read offline (d) photos on two devices
16. 16.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Science", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Science
17. 17.💾 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
18. 18.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) the sound on/off setting (d) a class leaderboard
19. 19.Which of these fits saving on the phone? (a) your last game level (b) a shared to-do list (c) photos on two devices (d) a class leaderboard
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Sports (c) Music
21. 21.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
22. 22.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
23. 23.💾 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
24. 24.💾 What number does this code show?
    let lives = 8;
    lives = lives - 4;
    lives = lives + 5;
    show(lives);
25. 25.💾 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
26. 26.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Art", "Science"];
    show(notes[2]); (a) Hindi (b) Science (c) Art
27. 27.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Hindi"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
28. 28.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Arjun", "Meera", "Aman", "Riya"];
    show(friends[4]); (a) Riya (b) Meera (c) Arjun (d) Zoya
29. 29.💾 What number does this code show?
    let notes = ["Sports", "Hindi"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
30. 30.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) a draft you are typing (d) chat messages to friends
31. 31.💾 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
32. 32.💾 What number does this code show?
    let lives = 5;
    lives = lives - 3;
    lives = lives + 1;
    show(lives);
33. 33.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) chat messages to friends (d) the sound on/off setting
34. 34.💾 What number does this code show?
    let points = 5;
    points = points - 2;
    points = points + 4;
    show(points);
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Meera", "Zoya", "Aman"];
    show(friends[1]); (a) Zoya (b) Arjun (c) Riya (d) Meera
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Riya", "Meera", "Aman", "Kabir"];
    show(friends[4]); (a) Kabir (b) Riya (c) Meera (d) Arjun
37. 37.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean"];
    songs.push("Monsoon");
    show(songs.length);
39. 39.💾 What number does this code show?
    let songs = ["Ocean", "Stars", "Sunrise"];
    songs.push("Rain");
    songs.push("Kites");
    show(songs.length);
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Art", "Hindi", "Music", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Art (d) Hindi

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