App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 743 · 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 photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 pop() takes off the last item. What does this code show?
   let notes = ["Sports", "Art", "Science", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Music (b) Art (c) Sports (d) Science
3. 3.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
4. 4.💾 What is a variable? (a) a type of screen (b) a picture (c) a named box for a value (d) a phone setting
5. 5.💾 What number does this code show?
   let points = 6;
   points = points - 3;
   points = points + 5;
   show(points);
6. 6.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) chat messages to friends (d) a draft you are typing
7. 7.💾 pop() takes off the last item. What does this code show?
   let songs = ["Sunrise", "Rain", "Kites", "Monsoon", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Monsoon (b) Rain (c) Kites (d) Sunrise
8. 8.💾 What number does this code show?
   let lives = 9;
   lives = lives - 8;
   lives = lives + 2;
   show(lives);
9. 9.💾 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
10. 10.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
11. 11.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
12. 12.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Monsoon", "Stars"];
    show(songs[2]); (a) Ocean (b) Stars (c) Monsoon
13. 13.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) your last game level
14. 14.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
15. 15.💾 What number does this code show?
    let notes = ["Hindi", "Sports", "Science"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
16. 16.💾 What number does this code show?
    let songs = ["Sunrise", "Stars", "Rain", "Ocean"];
    songs.push("Kites");
    songs.push("Monsoon");
    show(songs.length);
17. 17.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
18. 18.💾 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
19. 19.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
20. 20.💾 What number does this code show?
    let friends = ["Aman", "Kabir", "Meera", "Riya"];
    friends.push("Zoya");
    show(friends.length);
21. 21.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 5;
    show(lives);
22. 22.Which of these fits saving on the phone? (a) notes to read offline (b) chat messages to friends (c) a class leaderboard (d) photos on two devices
23. 23.💾 What number does this code show?
    let songs = ["Ocean", "Rain"];
    songs.push("Kites");
    show(songs.length);
24. 24.💾 What number does this code show?
    let songs = ["Kites", "Ocean", "Rain", "Monsoon"];
    songs.push("Sunrise");
    show(songs.length);
25. 25.True or false: your last game level fits saving in the cloud. (a) True (b) False
26. 26.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
27. 27.💾 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
28. 28.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
29. 29.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) a shared to-do list (d) your last game level
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Meera", "Zoya"];
    show(friends[0]); (a) Zoya (b) Meera (c) Riya
31. 31.💾 What number does this code show?
    let coins = 8;
    coins = coins - 7;
    coins = coins + 4;
    show(coins);
32. 32.💾 What number does this code show?
    let notes = ["Hindi", "Sports", "Maths", "Art"];
    notes.push("Science");
    notes.push("Music");
    show(notes.length);
33. 33.💾 What number does this code show?
    let friends = ["Riya", "Kabir"];
    friends.push("Aman");
    show(friends.length);
34. 34.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
35. 35.💾 What number does this code show?
    let score = 4;
    score = score - 4;
    score = score + 2;
    show(score);
36. 36.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) your last game level (d) photos on two devices
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Monsoon
38. 38.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
39. 39.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
40. 40.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) never need a password (d) use it on any device

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