App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 802 · 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 class leaderboard fits saving in the cloud. (a) True (b) False
2. 2.💾 What number does this code show?
   let score = 8;
   score = score - 8;
   score = score + 4;
   show(score);
3. 3.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
4. 4.💾 What number does this code show?
   let points = 5;
   points = points - 1;
   points = points + 1;
   show(points);
5. 5.True or false: your last game level fits saving on the phone. (a) True (b) False
6. 6.💾 What number does this code show?
   let lives = 7;
   lives = lives - 7;
   lives = lives + 1;
   show(lives);
7. 7.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
8. 8.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) a class leaderboard
9. 9.💾 What number does this code show?
   let friends = ["Meera", "Kabir", "Arjun"];
   friends.push("Riya");
   friends.push("Aman");
   show(friends.length);
10. 10.💾 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
11. 11.Which of these fits saving on the phone? (a) photos on two devices (b) a draft you are typing (c) chat messages to friends (d) a shared to-do list
12. 12.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) the sound on/off setting (d) photos on two devices
13. 13.💾 What number does this code show?
    let songs = ["Ocean", "Rain"];
    songs.push("Stars");
    show(songs.length);
14. 14.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
15. 15.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
16. 16.💾 What number does this code show?
    let notes = ["Hindi", "Maths"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
17. 17.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the app is closed (c) you send a message (d) the phone is lost
18. 18.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) never need a password (d) skip the internet
19. 19.💾 What number does this code show?
    let friends = ["Aman", "Zoya", "Arjun", "Kabir"];
    friends.push("Riya");
    friends.push("Meera");
    show(friends.length);
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Sports", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Maths (d) Art
21. 21.Which of these fits saving on the phone? (a) the sound on/off setting (b) chat messages to friends (c) a shared to-do list (d) a class leaderboard
22. 22.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
23. 23.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Arjun", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Arjun (c) Aman
24. 24.True or false: your last game level fits saving in the cloud. (a) True (b) False
25. 25.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
26. 26.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
27. 27.True or false: notes to read offline fits saving on the phone. (a) False (b) True
28. 28.Which of these fits saving on the phone? (a) notes to read offline (b) a class leaderboard (c) photos on two devices (d) a shared to-do list
29. 29.True or false: photos on two devices fits saving on the phone. (a) False (b) True
30. 30.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
31. 31.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) a class leaderboard (d) your last game level
32. 32.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a shared to-do list (d) a draft you are typing
33. 33.💾 What number does this code show?
    let score = 7;
    score = score - 2;
    score = score + 1;
    show(score);
34. 34.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Music", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Music (c) Maths (d) Science
35. 35.💾 What number does this code show?
    let score = 4;
    score = score - 1;
    score = score + 2;
    show(score);
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Ocean", "Kites", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Sunrise (c) Rain (d) Kites
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Hindi"];
    show(notes[0]); (a) Science (b) Maths (c) Hindi
38. 38.Which of these fits saving in the cloud? (a) your last game level (b) chat messages to friends (c) a draft you are typing (d) the sound on/off setting
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Rain", "Monsoon"];
    show(songs[1]); (a) Monsoon (b) Rain (c) Ocean
40. 40.💾 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

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