App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 787 · 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 in the cloud? (a) a shared to-do list (b) notes to read offline (c) your last game level (d) a draft you are typing
2. 2.💾 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
3. 3.Which of these fits saving on the phone? (a) the sound on/off setting (b) photos on two devices (c) a shared to-do list (d) a class leaderboard
4. 4.💾 What does this code show? (Positions start at 0.)
   let notes = ["Music", "Art", "Sports"];
   show(notes[2]); (a) Art (b) Music (c) Sports
5. 5.💾 What number does this code show?
   let notes = ["Music", "Maths", "Art"];
   notes.push("Hindi");
   notes.push("Sports");
   show(notes.length);
6. 6.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
7. 7.💾 What number does this code show?
   let score = 8;
   score = score - 8;
   score = score + 1;
   show(score);
8. 8.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.💾 What number does this code show?
   let stars = 4;
   stars = stars - 3;
   stars = stars + 2;
   show(stars);
10. 10.💾 Which can hold many values in order? (a) a button (b) a switch (c) a list (d) a single number
11. 11.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
12. 12.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.💾 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
14. 14.💾 What number does this code show?
    let friends = ["Kabir", "Zoya", "Riya"];
    friends.push("Aman");
    show(friends.length);
15. 15.💾 What number does this code show?
    let notes = ["Music", "Art"];
    notes.push("Maths");
    notes.push("Science");
    show(notes.length);
16. 16.💾 What number does this code show?
    let notes = ["Science", "Maths", "Art", "Music"];
    notes.push("Sports");
    show(notes.length);
17. 17.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
18. 18.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Ocean"];
    songs.push("Kites");
    songs.push("Sunrise");
    show(songs.length);
19. 19.💾 What number does this code show?
    let notes = ["Art", "Maths", "Science", "Sports"];
    notes.push("Hindi");
    show(notes.length);
20. 20.💾 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
21. 21.💾 What number does this code show?
    let lives = 3;
    lives = lives - 2;
    lives = lives + 1;
    show(lives);
22. 22.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Ocean", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Kites (c) Rain (d) Sunrise
23. 23.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) notes to read offline
24. 24.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
25. 25.Which of these fits saving in the cloud? (a) a class leaderboard (b) your last game level (c) notes to read offline (d) a draft you are typing
26. 26.💾 What number does this code show?
    let songs = ["Ocean", "Kites", "Monsoon", "Rain"];
    songs.push("Sunrise");
    show(songs.length);
27. 27.True or false: your last game level fits saving in the cloud. (a) True (b) False
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Hindi", "Sports"];
    show(notes[0]); (a) Sports (b) Music (c) Hindi
29. 29.💾 What number does this code show?
    let coins = 4;
    coins = coins - 3;
    coins = coins + 5;
    show(coins);
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Kabir"];
    show(friends[0]); (a) Arjun (b) Riya (c) Kabir
31. 31.💾 What is a variable? (a) a picture (b) a phone setting (c) a named box for a value (d) a type of screen
32. 32.💾 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
33. 33.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Monsoon", "Sunrise", "Stars"];
    show(songs[0]); (a) Kites (b) Monsoon (c) Stars (d) Sunrise
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Zoya", "Aman"];
    show(friends[2]); (a) Riya (b) Aman (c) Zoya
35. 35.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
36. 36.💾 What number does this code show?
    let friends = ["Meera", "Riya"];
    friends.push("Arjun");
    friends.push("Kabir");
    show(friends.length);
37. 37.Which of these fits saving in the cloud? (a) photos on two devices (b) a draft you are typing (c) the sound on/off setting (d) notes to read offline
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Art", "Hindi"];
    show(notes[1]); (a) Hindi (b) Art (c) Music
39. 39.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
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Music", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Maths (c) Hindi

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