App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 171 · 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.💾 What is a variable? (a) a type of screen (b) a picture (c) a named box for a value (d) a phone setting
2. 2.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.True or false: your last game level fits saving on the phone. (a) True (b) False
4. 4.True or false: your last game level fits saving in the cloud. (a) True (b) False
5. 5.Which of these fits saving in the cloud? (a) your last game level (b) chat messages to friends (c) the sound on/off setting (d) notes to read offline
6. 6.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
7. 7.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
8. 8.💾 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
9. 9.💾 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
10. 10.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) notes to read offline (d) a shared to-do list
12. 12.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) a shared to-do list (d) your last game level
13. 13.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) notes to read offline (d) photos on two devices
14. 14.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Kites", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Monsoon (c) Kites
15. 15.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
16. 16.💾 What number does this code show?
    let lives = 4;
    lives = lives - 1;
    lives = lives + 3;
    show(lives);
17. 17.💾 What number does this code show?
    let coins = 3;
    coins = coins - 2;
    coins = coins + 4;
    show(coins);
18. 18.Which of these fits saving in the cloud? (a) your last game level (b) a class leaderboard (c) a draft you are typing (d) the sound on/off setting
19. 19.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
20. 20.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
21. 21.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Meera", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Meera (c) Riya
22. 22.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
23. 23.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 0 (c) 1 (d) 10
24. 24.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
25. 25.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a shared to-do list (d) a class leaderboard
26. 26.💾 What number does this code show?
    let stars = 9;
    stars = stars - 8;
    stars = stars + 2;
    show(stars);
27. 27.💾 What number does this code show?
    let friends = ["Aman", "Riya"];
    friends.push("Zoya");
    show(friends.length);
28. 28.💾 What number does this code show?
    let friends = ["Meera", "Zoya"];
    friends.push("Riya");
    friends.push("Arjun");
    show(friends.length);
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Ocean", "Rain", "Stars", "Sunrise"];
    show(songs[1]); (a) Monsoon (b) Stars (c) Ocean (d) Rain
30. 30.💾 What number does this code show?
    let songs = ["Ocean", "Rain", "Kites", "Sunrise"];
    songs.push("Stars");
    show(songs.length);
31. 31.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
32. 32.💾 What number does this code show?
    let lives = 5;
    lives = lives - 5;
    lives = lives + 5;
    show(lives);
33. 33.💾 What number does this code show?
    let notes = ["Art", "Maths", "Science"];
    notes.push("Music");
    notes.push("Hindi");
    show(notes.length);
34. 34.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
35. 35.💾 What number does this code show?
    let points = 5;
    points = points - 5;
    points = points + 4;
    show(points);
36. 36.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Monsoon", "Stars"];
    show(songs[1]); (a) Rain (b) Stars (c) Monsoon (d) Sunrise
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Rain", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Monsoon (c) Sunrise (d) Kites
38. 38.💾 What number does this code show?
    let songs = ["Stars", "Ocean", "Sunrise", "Monsoon"];
    songs.push("Kites");
    show(songs.length);
39. 39.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
40. 40.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) data saved on the phone (d) a shared chat

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