App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 907 · 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.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
3. 3.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
4. 4.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a draft you are typing (d) a shared to-do list
5. 5.💾 Where should the app save chat messages to friends: 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) a draft you are typing (b) a shared to-do list (c) a class leaderboard (d) photos on two devices
7. 7.💾 What number does this code show?
   let songs = ["Stars", "Sunrise"];
   songs.push("Rain");
   show(songs.length);
8. 8.💾 What number does this code show?
   let coins = 5;
   coins = coins - 2;
   coins = coins + 1;
   show(coins);
9. 9.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
10. 10.💾 What number does this code show?
    let songs = ["Kites", "Rain"];
    songs.push("Ocean");
    show(songs.length);
11. 11.💾 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
12. 12.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Monsoon", "Rain", "Stars"];
    show(songs[3]); (a) Sunrise (b) Kites (c) Rain (d) Monsoon
13. 13.Which of these fits saving in the cloud? (a) chat messages to friends (b) your last game level (c) a draft you are typing (d) the sound on/off setting
14. 14.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
15. 15.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Arjun", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Riya (c) Aman (d) Zoya
16. 16.True or false: notes to read offline fits saving on the phone. (a) False (b) True
17. 17.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
18. 18.True or false: your last game level fits saving on the phone. (a) False (b) True
19. 19.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
20. 20.💾 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
21. 21.💾 What number does this code show?
    let friends = ["Kabir", "Zoya", "Aman"];
    friends.push("Meera");
    friends.push("Arjun");
    show(friends.length);
22. 22.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the app is closed (c) the phone is lost (d) you send a message
23. 23.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) skip the internet (d) never need a password
24. 24.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Aman", "Arjun", "Riya"];
    show(friends[0]); (a) Riya (b) Zoya (c) Aman (d) Arjun
25. 25.💾 What number does this code show?
    let notes = ["Science", "Hindi"];
    notes.push("Music");
    notes.push("Sports");
    show(notes.length);
26. 26.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 0 (d) 10
27. 27.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Stars", "Ocean"];
    show(songs[1]); (a) Ocean (b) Stars (c) Rain
28. 28.💾 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
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Sunrise", "Monsoon", "Kites"];
    show(songs[1]); (a) Stars (b) Kites (c) Sunrise (d) Monsoon
30. 30.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
31. 31.Which of these fits saving on the phone? (a) the sound on/off setting (b) a class leaderboard (c) chat messages to friends (d) a shared to-do list
32. 32.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) a class leaderboard (d) your last game level
33. 33.Which of these fits saving in the cloud? (a) a draft you are typing (b) a class leaderboard (c) the sound on/off setting (d) notes to read offline
34. 34.💾 What number does this code show?
    let songs = ["Monsoon", "Rain", "Ocean"];
    songs.push("Stars");
    show(songs.length);
35. 35.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
36. 36.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) notes to read offline (d) a class leaderboard
37. 37.💾 What number does this code show?
    let songs = ["Rain", "Sunrise"];
    songs.push("Kites");
    show(songs.length);
38. 38.💾 What number does this code show?
    let notes = ["Hindi", "Science", "Sports"];
    notes.push("Music");
    show(notes.length);
39. 39.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise", "Rain", "Kites"];
    songs.push("Stars");
    show(songs.length);
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Zoya", "Riya"];
    show(friends[0]); (a) Zoya (b) Riya (c) Kabir

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