App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 95 · 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 a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) a class leaderboard (d) a draft you are typing
3. 3.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
4. 4.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
5. 5.💾 What number does this code show?
   let songs = ["Stars", "Ocean", "Monsoon", "Kites"];
   songs.push("Sunrise");
   songs.push("Rain");
   show(songs.length);
6. 6.💾 What number does this code show?
   let songs = ["Stars", "Ocean", "Kites"];
   songs.push("Sunrise");
   songs.push("Rain");
   show(songs.length);
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Hindi", "Art", "Sports", "Science", "Maths"];
   show(notes[1]); (a) Art (b) Sports (c) Science (d) Hindi
8. 8.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) shrink the app (d) use it on any device
9. 9.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
10. 10.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Science", "Hindi", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Art (c) Music (d) Hindi
11. 11.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) chat messages to friends (d) a shared to-do list
12. 12.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a picture (d) a named box for a value
13. 13.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 2;
    show(points);
14. 14.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the phone is lost (d) the app is closed
15. 15.💾 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
16. 16.💾 What number does this code show?
    let friends = ["Arjun", "Riya"];
    friends.push("Meera");
    show(friends.length);
17. 17.💾 What number does this code show?
    let lives = 8;
    lives = lives - 8;
    lives = lives + 5;
    show(lives);
18. 18.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Art", "Maths"];
    show(notes[0]); (a) Maths (b) Music (c) Art
19. 19.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.True or false: your last game level fits saving on the phone. (a) True (b) False
21. 21.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Kites (c) Ocean
22. 22.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 2;
    show(coins);
23. 23.💾 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
24. 24.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Ocean", "Sunrise", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Kites (c) Ocean (d) Sunrise
25. 25.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Art"];
    notes.push("Science");
    notes.push("Hindi");
    show(notes.length);
26. 26.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) chat messages to friends (d) your last game level
27. 27.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a draft you are typing (d) photos on two devices
28. 28.💾 What number does this code show?
    let coins = 7;
    coins = coins - 3;
    coins = coins + 4;
    show(coins);
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Maths", "Music"];
    show(notes[0]); (a) Art (b) Music (c) Maths
30. 30.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
31. 31.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Stars", "Kites", "Rain"];
    show(songs[0]); (a) Sunrise (b) Stars (c) Rain (d) Kites
32. 32.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) a draft you are typing (d) a shared to-do list
33. 33.💾 Which can hold many values in order? (a) a switch (b) a list (c) a button (d) a single number
34. 34.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 1;
    show(points);
35. 35.💾 What number does this code show?
    let stars = 7;
    stars = stars - 1;
    stars = stars + 2;
    show(stars);
36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Hindi (c) Art
37. 37.True or false: notes to read offline fits saving on the phone. (a) True (b) False
38. 38.True or false: photos on two devices fits saving on the phone. (a) False (b) True
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Sports", "Science", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Sports (d) Science
40. 40.True or false: your last game level fits saving in the cloud. (a) False (b) True

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