App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 448 · 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.True or false: your last game level fits saving in the cloud. (a) False (b) True
2. 2.💾 What does this code show? (Positions start at 0.)
   let songs = ["Sunrise", "Ocean", "Kites", "Rain"];
   show(songs[1]); (a) Rain (b) Sunrise (c) Ocean (d) Kites
3. 3.True or false: your last game level fits saving on the phone. (a) True (b) False
4. 4.Which of these fits saving on the phone? (a) chat messages to friends (b) a draft you are typing (c) a shared to-do list (d) photos on two devices
5. 5.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
6. 6.💾 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
7. 7.💾 What number does this code show?
   let friends = ["Meera", "Arjun"];
   friends.push("Zoya");
   friends.push("Riya");
   show(friends.length);
8. 8.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) data saved on the phone (d) a cloud leaderboard
9. 9.💾 pop() takes off the last item. What does this code show?
   let friends = ["Meera", "Arjun", "Kabir"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Kabir (b) Meera (c) Arjun
10. 10.💾 What is a variable? (a) a named box for a value (b) a type of screen (c) a picture (d) a phone setting
11. 11.True or false: photos on two devices fits saving on the phone. (a) False (b) True
12. 12.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
13. 13.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Rain", "Sunrise", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Rain (c) Ocean (d) Sunrise
14. 14.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) chat messages to friends (d) the sound on/off setting
15. 15.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Zoya", "Meera", "Aman"];
    show(friends[3]); (a) Zoya (b) Aman (c) Kabir (d) Meera
16. 16.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
17. 17.💾 What number does this code show?
    let coins = 3;
    coins = coins - 2;
    coins = coins + 3;
    show(coins);
18. 18.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
19. 19.Which of these fits saving on the phone? (a) chat messages to friends (b) your last game level (c) a shared to-do list (d) a class leaderboard
20. 20.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 4;
    show(score);
21. 21.Which of these fits saving in the cloud? (a) a draft you are typing (b) a shared to-do list (c) notes to read offline (d) the sound on/off setting
22. 22.💾 What number does this code show?
    let friends = ["Arjun", "Zoya"];
    friends.push("Riya");
    show(friends.length);
23. 23.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
24. 24.Which of these fits saving in the cloud? (a) photos on two devices (b) your last game level (c) the sound on/off setting (d) notes to read offline
25. 25.💾 What number does this code show?
    let songs = ["Sunrise", "Stars", "Rain", "Ocean"];
    songs.push("Monsoon");
    show(songs.length);
26. 26.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.Which of these fits saving on the phone? (a) notes to read offline (b) a class leaderboard (c) chat messages to friends (d) a shared to-do list
28. 28.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Sunrise (c) Rain
29. 29.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Stars
31. 31.💾 What number does this code show?
    let coins = 7;
    coins = coins - 2;
    coins = coins + 5;
    show(coins);
32. 32.💾 What number does this code show?
    let points = 5;
    points = points - 2;
    points = points + 4;
    show(points);
33. 33.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
34. 34.💾 What number does this code show?
    let lives = 5;
    lives = lives - 2;
    lives = lives + 4;
    show(lives);
35. 35.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Monsoon", "Stars", "Sunrise", "Ocean"];
    show(songs[4]); (a) Kites (b) Ocean (c) Monsoon (d) Stars
36. 36.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) chat messages to friends (d) a draft you are typing
37. 37.💾 Which can hold many values in order? (a) a list (b) a single number (c) a button (d) a switch
38. 38.💾 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
39. 39.💾 What number does this code show?
    let score = 7;
    score = score - 1;
    score = score + 1;
    show(score);
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Zoya", "Meera", "Riya"];
    show(friends[3]); (a) Aman (b) Kabir (c) Zoya (d) Meera

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