App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 712 · 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.💾 pop() takes off the last item. What does this code show?
   let notes = ["Sports", "Science", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Music (c) Science
2. 2.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
3. 3.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) photos on two devices (d) the sound on/off setting
4. 4.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
5. 5.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
6. 6.Which of these fits saving on the phone? (a) notes to read offline (b) photos on two devices (c) chat messages to friends (d) a class leaderboard
7. 7.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the phone is lost (c) the app is closed (d) the screen turns off
8. 8.💾 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
9. 9.💾 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
10. 10.💾 What number does this code show?
    let score = 9;
    score = score - 4;
    score = score + 3;
    show(score);
11. 11.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a button (d) a list
12. 12.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Riya", "Meera", "Kabir"];
    show(friends[0]); (a) Meera (b) Kabir (c) Zoya (d) Riya
13. 13.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 1 (c) 10 (d) 0
14. 14.💾 What is a variable? (a) a picture (b) a phone setting (c) a type of screen (d) a named box for a value
15. 15.💾 What number does this code show?
    let songs = ["Sunrise", "Monsoon"];
    songs.push("Rain");
    show(songs.length);
16. 16.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Stars (c) Rain (d) Monsoon
17. 17.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Zoya", "Riya"];
    show(friends[2]); (a) Zoya (b) Riya (c) Meera
18. 18.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
19. 19.💾 What number does this code show?
    let notes = ["Sports", "Music"];
    notes.push("Art");
    show(notes.length);
20. 20.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 1;
    show(score);
21. 21.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Kabir", "Riya", "Aman", "Arjun"];
    show(friends[3]); (a) Aman (b) Kabir (c) Riya (d) Zoya
22. 22.💾 What number does this code show?
    let songs = ["Kites", "Rain", "Ocean"];
    songs.push("Monsoon");
    songs.push("Sunrise");
    show(songs.length);
23. 23.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a cloud backup (c) data saved on the phone (d) a shared chat
24. 24.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
25. 25.💾 What number does this code show?
    let stars = 7;
    stars = stars - 3;
    stars = stars + 5;
    show(stars);
26. 26.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Riya", "Zoya"];
    show(friends[2]); (a) Zoya (b) Riya (c) Aman
27. 27.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
28. 28.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Sunrise", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Monsoon (c) Ocean (d) Sunrise
29. 29.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 5;
    show(score);
30. 30.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 5;
    show(lives);
31. 31.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) a class leaderboard
32. 32.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) chat messages to friends
33. 33.True or false: your last game level fits saving in the cloud. (a) False (b) True
34. 34.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Stars", "Monsoon", "Rain", "Kites"];
    show(songs[2]); (a) Monsoon (b) Sunrise (c) Rain (d) Stars
35. 35.💾 What number does this code show?
    let coins = 9;
    coins = coins - 6;
    coins = coins + 3;
    show(coins);
36. 36.Which of these fits saving on the phone? (a) your last game level (b) a shared to-do list (c) chat messages to friends (d) a class leaderboard
37. 37.💾 What number does this code show?
    let stars = 4;
    stars = stars - 1;
    stars = stars + 4;
    show(stars);
38. 38.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
39. 39.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
40. 40.True or false: a draft you are typing fits saving on the phone. (a) False (b) True

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