App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 559 · 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 of these fits saving on the phone? (a) photos on two devices (b) the sound on/off setting (c) a shared to-do list (d) a class leaderboard
2. 2.💾 What number does this code show?
   let stars = 5;
   stars = stars - 3;
   stars = stars + 4;
   show(stars);
3. 3.Which of these fits saving in the cloud? (a) notes to read offline (b) a class leaderboard (c) your last game level (d) the sound on/off setting
4. 4.Which of these fits saving in the cloud? (a) photos on two devices (b) your last game level (c) notes to read offline (d) a draft you are typing
5. 5.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) photos on two devices (d) a draft you are typing
6. 6.💾 What is a variable? (a) a type of screen (b) a named box for a value (c) a picture (d) a phone setting
7. 7.💾 pop() takes off the last item. What does this code show?
   let notes = ["Maths", "Art", "Sports", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Art (c) Sports (d) Music
8. 8.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Sports", "Art", "Hindi", "Maths"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Science (d) Art
9. 9.💾 pop() takes off the last item. What does this code show?
   let songs = ["Monsoon", "Kites", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Monsoon (b) Stars (c) Kites
10. 10.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) you send a message (c) the app is closed (d) the phone is lost
11. 11.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
12. 12.💾 What number does this code show?
    let lives = 7;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
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.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Sports", "Hindi"];
    show(notes[0]); (a) Science (b) Sports (c) Hindi
15. 15.💾 What number does this code show?
    let stars = 7;
    stars = stars - 4;
    stars = stars + 3;
    show(stars);
16. 16.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
17. 17.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
18. 18.💾 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
19. 19.💾 What number does this code show?
    let lives = 5;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
20. 20.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
21. 21.💾 What number does this code show?
    let notes = ["Science", "Hindi", "Art"];
    notes.push("Music");
    show(notes.length);
22. 22.💾 What number does this code show?
    let coins = 8;
    coins = coins - 5;
    coins = coins + 2;
    show(coins);
23. 23.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Rain", "Stars"];
    show(songs[2]); (a) Rain (b) Ocean (c) Stars
24. 24.💾 What number does this code show?
    let friends = ["Riya", "Zoya"];
    friends.push("Aman");
    show(friends.length);
25. 25.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) your last game level
26. 26.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
27. 27.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Music", "Maths", "Sports"];
    show(notes[2]); (a) Maths (b) Sports (c) Music (d) Hindi
29. 29.💾 What number does this code show?
    let songs = ["Sunrise", "Stars"];
    songs.push("Monsoon");
    songs.push("Rain");
    show(songs.length);
30. 30.💾 What number does this code show?
    let score = 9;
    score = score - 6;
    score = score + 1;
    show(score);
31. 31.💾 What number does this code show?
    let notes = ["Music", "Maths"];
    notes.push("Sports");
    show(notes.length);
32. 32.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Science", "Sports", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Art (c) Maths (d) Sports
34. 34.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 0 (c) 10 (d) 2
35. 35.💾 What number does this code show?
    let lives = 4;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
36. 36.True or false: your last game level fits saving on the phone. (a) False (b) True
37. 37.💾 What number does this code show?
    let points = 3;
    points = points - 1;
    points = points + 4;
    show(points);
38. 38.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Monsoon", "Stars", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Monsoon (c) Rain (d) Sunrise
39. 39.💾 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
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Music", "Maths", "Sports", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Maths (d) Art

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