App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 405 · 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.💾 pop() takes off the last item. What does this code show?
   let friends = ["Arjun", "Riya", "Kabir", "Aman"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Kabir (b) Aman (c) Arjun (d) Riya
2. 2.💾 What number does this code show?
   let coins = 3;
   coins = coins - 2;
   coins = coins + 5;
   show(coins);
3. 3.💾 What number does this code show?
   let points = 7;
   points = points - 4;
   points = points + 5;
   show(points);
4. 4.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) your last game level (d) photos on two devices
5. 5.💾 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
6. 6.💾 What number does this code show?
   let coins = 4;
   coins = coins - 1;
   coins = coins + 3;
   show(coins);
7. 7.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) never need a password (c) shrink the app (d) use it on any device
8. 8.💾 What number does this code show?
   let lives = 4;
   lives = lives - 1;
   lives = lives + 1;
   show(lives);
9. 9.💾 What does this code show? (Positions start at 0.)
   let notes = ["Maths", "Sports", "Art", "Science"];
   show(notes[0]); (a) Sports (b) Maths (c) Art (d) Science
10. 10.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the screen turns off (c) the app is closed (d) you send a message
11. 11.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
12. 12.💾 What number does this code show?
    let friends = ["Zoya", "Riya"];
    friends.push("Aman");
    friends.push("Meera");
    show(friends.length);
13. 13.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
14. 14.💾 What number does this code show?
    let notes = ["Music", "Sports"];
    notes.push("Science");
    notes.push("Art");
    show(notes.length);
15. 15.💾 What number does this code show?
    let notes = ["Art", "Science"];
    notes.push("Sports");
    show(notes.length);
16. 16.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Music", "Science", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Art (c) Music (d) Maths
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Art", "Hindi"];
    show(notes[1]); (a) Science (b) Hindi (c) Art
18. 18.💾 What number does this code show?
    let lives = 4;
    lives = lives - 1;
    lives = lives + 4;
    show(lives);
19. 19.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) photos on two devices (d) your last game level
20. 20.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a type of screen (d) a picture
21. 21.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud backup (d) a cloud leaderboard
22. 22.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 2;
    show(score);
23. 23.💾 What number does this code show?
    let lives = 9;
    lives = lives - 3;
    lives = lives + 5;
    show(lives);
24. 24.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
25. 25.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) a class leaderboard (d) a draft you are typing
26. 26.💾 What number does this code show?
    let notes = ["Sports", "Maths", "Hindi"];
    notes.push("Music");
    show(notes.length);
27. 27.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
28. 28.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Kabir", "Riya"];
    show(friends[1]); (a) Kabir (b) Riya (c) Zoya
29. 29.True or false: notes to read offline fits saving on the phone. (a) True (b) False
30. 30.💾 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
31. 31.💾 What number does this code show?
    let songs = ["Kites", "Rain", "Stars"];
    songs.push("Sunrise");
    show(songs.length);
32. 32.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
33. 33.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
34. 34.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) notes to read offline (d) photos on two devices
35. 35.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Sunrise", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Rain (c) Monsoon
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Riya", "Aman"];
    show(friends[2]); (a) Arjun (b) Riya (c) Aman
37. 37.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.💾 What number does this code show?
    let friends = ["Aman", "Zoya", "Meera", "Riya"];
    friends.push("Kabir");
    show(friends.length);
39. 39.True or false: your last game level fits saving in the cloud. (a) False (b) True
40. 40.💾 What number does this code show?
    let notes = ["Hindi", "Music", "Sports"];
    notes.push("Maths");
    show(notes.length);

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