App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 453 · 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.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.💾 What number does this code show?
   let notes = ["Maths", "Art", "Music", "Sports"];
   notes.push("Hindi");
   show(notes.length);
4. 4.💾 What number does this code show?
   let songs = ["Rain", "Sunrise", "Ocean", "Monsoon"];
   songs.push("Kites");
   show(songs.length);
5. 5.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) a class leaderboard
6. 6.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
7. 7.💾 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
8. 8.Which of these fits saving on the phone? (a) photos on two devices (b) a draft you are typing (c) a shared to-do list (d) chat messages to friends
9. 9.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a class leaderboard (d) a shared to-do list
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.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Kites", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Sunrise
12. 12.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a picture (d) a type of screen
13. 13.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Art", "Maths", "Hindi"];
    show(notes[2]); (a) Music (b) Maths (c) Art (d) Science
14. 14.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 1;
    show(stars);
15. 15.💾 What number does this code show?
    let notes = ["Music", "Hindi", "Sports", "Science"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
16. 16.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 2;
    show(points);
17. 17.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Stars", "Monsoon", "Rain"];
    show(songs[3]); (a) Rain (b) Kites (c) Monsoon (d) Stars
18. 18.True or false: notes to read offline fits saving on the phone. (a) False (b) True
19. 19.💾 What number does this code show?
    let points = 5;
    points = points - 1;
    points = points + 1;
    show(points);
20. 20.💾 What number does this code show?
    let points = 9;
    points = points - 3;
    points = points + 1;
    show(points);
21. 21.True or false: photos on two devices fits saving on the phone. (a) False (b) True
22. 22.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) a shared to-do list (d) the sound on/off setting
23. 23.💾 What number does this code show?
    let notes = ["Art", "Hindi"];
    notes.push("Sports");
    notes.push("Science");
    show(notes.length);
24. 24.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
25. 25.💾 What number does this code show?
    let songs = ["Monsoon", "Stars", "Rain"];
    songs.push("Sunrise");
    show(songs.length);
26. 26.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Meera", "Kabir", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Arjun (d) Meera
27. 27.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Meera", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Meera (c) Aman (d) Zoya
28. 28.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
29. 29.💾 What number does this code show?
    let songs = ["Kites", "Ocean", "Monsoon", "Stars"];
    songs.push("Sunrise");
    show(songs.length);
30. 30.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Riya", "Zoya", "Meera", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Riya (c) Meera (d) Kabir
31. 31.💾 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
32. 32.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
33. 33.💾 What number does this code show?
    let lives = 9;
    lives = lives - 9;
    lives = lives + 3;
    show(lives);
34. 34.💾 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
35. 35.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) a class leaderboard (d) photos on two devices
36. 36.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Sports", "Maths", "Science"];
    show(notes[0]); (a) Sports (b) Science (c) Hindi (d) Maths
37. 37.💾 What number does this code show?
    let notes = ["Art", "Music"];
    notes.push("Maths");
    show(notes.length);
38. 38.💾 What number does this code show?
    let notes = ["Sports", "Art"];
    notes.push("Science");
    show(notes.length);
39. 39.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
40. 40.True or false: photos on two devices fits saving in the cloud. (a) True (b) False

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