App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 100 · 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: a shared to-do list fits saving in the cloud. (a) False (b) True
2. 2.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.💾 pop() takes off the last item. What does this code show?
   let notes = ["Maths", "Art", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Art (c) Hindi
4. 4.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
5. 5.💾 What does this code show? (Positions start at 0.)
   let friends = ["Meera", "Arjun", "Riya", "Zoya"];
   show(friends[2]); (a) Riya (b) Zoya (c) Arjun (d) Meera
6. 6.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
7. 7.💾 What number does this code show?
   let score = 5;
   score = score - 2;
   score = score + 5;
   show(score);
8. 8.Which of these fits saving on the phone? (a) a class leaderboard (b) notes to read offline (c) a shared to-do list (d) chat messages to friends
9. 9.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) photos on two devices (d) a draft you are typing
10. 10.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
11. 11.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
12. 12.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Art (c) Hindi (d) Sports
13. 13.💾 What number does this code show?
    let coins = 7;
    coins = coins - 3;
    coins = coins + 1;
    show(coins);
14. 14.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Hindi", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Maths (c) Hindi (d) Sports
15. 15.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
16. 16.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud backup (c) a shared chat (d) a cloud leaderboard
17. 17.💾 What number does this code show?
    let stars = 8;
    stars = stars - 7;
    stars = stars + 2;
    show(stars);
18. 18.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
19. 19.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Riya", "Meera", "Arjun"];
    show(friends[0]); (a) Aman (b) Riya (c) Kabir (d) Meera
20. 20.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Aman", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Meera (c) Aman
21. 21.💾 What number does this code show?
    let notes = ["Art", "Science", "Hindi"];
    notes.push("Maths");
    notes.push("Sports");
    show(notes.length);
22. 22.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Zoya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Zoya (c) Riya
23. 23.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
24. 24.💾 What number does this code show?
    let songs = ["Rain", "Ocean"];
    songs.push("Stars");
    show(songs.length);
25. 25.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the phone is lost (d) the screen turns off
26. 26.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
28. 28.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Arjun", "Riya", "Zoya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Zoya (c) Arjun (d) Meera
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Science
30. 30.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
31. 31.True or false: your last game level fits saving on the phone. (a) False (b) True
32. 32.💾 What number does this code show?
    let lives = 6;
    lives = lives - 4;
    lives = lives + 4;
    show(lives);
33. 33.💾 What is a variable? (a) a picture (b) a type of screen (c) a named box for a value (d) a phone setting
34. 34.Which of these fits saving on the phone? (a) the sound on/off setting (b) a class leaderboard (c) chat messages to friends (d) photos on two devices
35. 35.💾 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
36. 36.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Ocean"];
    show(songs[1]); (a) Sunrise (b) Ocean (c) Rain
37. 37.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a shared to-do list (d) a draft you are typing
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Art", "Science", "Sports"];
    show(notes[1]); (a) Art (b) Hindi (c) Science (d) Maths
39. 39.True or false: your last game level fits saving in the cloud. (a) False (b) True
40. 40.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) notes to read offline (d) a class leaderboard

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