App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 510 · 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.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a shared chat (d) a cloud backup
2. 2.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) chat messages to friends (d) notes to read offline
4. 4.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) use it on any device (c) shrink the app (d) never need a password
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.True or false: photos on two devices fits saving on the phone. (a) True (b) False
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Music", "Sports", "Maths", "Hindi", "Art"];
   show(notes[1]); (a) Maths (b) Sports (c) Music (d) Hindi
8. 8.💾 What number does this code show?
   let points = 5;
   points = points - 5;
   points = points + 3;
   show(points);
9. 9.💾 What number does this code show?
   let notes = ["Science", "Art"];
   notes.push("Music");
   notes.push("Hindi");
   show(notes.length);
10. 10.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Science", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Science (c) Hindi
11. 11.💾 What number does this code show?
    let notes = ["Hindi", "Sports", "Science"];
    notes.push("Music");
    show(notes.length);
12. 12.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
13. 13.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
14. 14.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) photos on two devices (d) chat messages to friends
15. 15.💾 What number does this code show?
    let coins = 8;
    coins = coins - 1;
    coins = coins + 4;
    show(coins);
16. 16.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a shared to-do list (d) the sound on/off setting
17. 17.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
18. 18.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
19. 19.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Rain", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Monsoon (c) Rain
20. 20.💾 What number does this code show?
    let songs = ["Monsoon", "Kites", "Sunrise", "Ocean"];
    songs.push("Stars");
    show(songs.length);
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.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) the sound on/off setting (d) a shared to-do list
23. 23.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
24. 24.💾 What is a variable? (a) a picture (b) a phone setting (c) a type of screen (d) a named box for a value
25. 25.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 1 (d) 10
26. 26.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
27. 27.💾 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
28. 28.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) the phone is lost (d) you send a message
29. 29.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
30. 30.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
31. 31.💾 What number does this code show?
    let friends = ["Aman", "Zoya", "Riya"];
    friends.push("Arjun");
    show(friends.length);
32. 32.💾 What number does this code show?
    let score = 7;
    score = score - 4;
    score = score + 5;
    show(score);
33. 33.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon", "Sunrise"];
    songs.push("Stars");
    show(songs.length);
34. 34.💾 What number does this code show?
    let friends = ["Riya", "Arjun", "Kabir", "Meera"];
    friends.push("Aman");
    show(friends.length);
35. 35.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) a shared to-do list (d) a draft you are typing
36. 36.💾 What number does this code show?
    let friends = ["Riya", "Meera", "Aman", "Zoya"];
    friends.push("Arjun");
    friends.push("Kabir");
    show(friends.length);
37. 37.True or false: notes to read offline fits saving on the phone. (a) True (b) False
38. 38.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 4;
    show(stars);
39. 39.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) notes to read offline (d) photos on two devices
40. 40.💾 What number does this code show?
    let lives = 7;
    lives = lives - 1;
    lives = lives + 3;
    show(lives);

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