App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 61 · 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 on the phone? (a) your last game level (b) a class leaderboard (c) photos on two devices (d) a shared to-do list
2. 2.True or false: photos on two devices fits saving on the phone. (a) True (b) False
3. 3.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
4. 4.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) never need a password (c) use it on any device (d) skip the internet
5. 5.💾 Which can hold many values in order? (a) a button (b) a single number (c) a list (d) a switch
6. 6.💾 What number does this code show?
   let songs = ["Stars", "Ocean", "Sunrise", "Kites"];
   songs.push("Rain");
   songs.push("Monsoon");
   show(songs.length);
7. 7.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 0 (d) 2
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.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Science", "Maths", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Art (c) Music (d) Science
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Ocean", "Monsoon", "Stars"];
    show(songs[2]); (a) Sunrise (b) Rain (c) Monsoon (d) Ocean
11. 11.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Kabir", "Zoya", "Arjun"];
    show(friends[0]); (a) Riya (b) Arjun (c) Kabir (d) Zoya
12. 12.True or false: your last game level fits saving in the cloud. (a) False (b) True
13. 13.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) a shared to-do list (d) your last game level
14. 14.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) chat messages to friends (d) notes to read offline
15. 15.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a named box for a value (d) a picture
16. 16.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) your last game level (d) a class leaderboard
17. 17.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the phone is lost (d) the screen turns off
18. 18.💾 What number does this code show?
    let coins = 5;
    coins = coins - 5;
    coins = coins + 1;
    show(coins);
19. 19.💾 What number does this code show?
    let friends = ["Riya", "Kabir", "Arjun", "Zoya"];
    friends.push("Aman");
    friends.push("Meera");
    show(friends.length);
20. 20.💾 What number does this code show?
    let stars = 7;
    stars = stars - 2;
    stars = stars + 3;
    show(stars);
21. 21.💾 What number does this code show?
    let points = 8;
    points = points - 4;
    points = points + 5;
    show(points);
22. 22.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
23. 23.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
24. 24.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
25. 25.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
26. 26.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Monsoon", "Stars", "Kites", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Kites (c) Rain (d) Monsoon
27. 27.💾 What number does this code show?
    let notes = ["Science", "Music"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
28. 28.True or false: notes to read offline fits saving on the phone. (a) False (b) True
29. 29.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a shared chat (d) a cloud backup
30. 30.Which of these fits saving in the cloud? (a) photos on two devices (b) the sound on/off setting (c) notes to read offline (d) a draft you are typing
31. 31.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean", "Monsoon", "Rain"];
    songs.push("Kites");
    songs.push("Stars");
    show(songs.length);
32. 32.💾 What number does this code show?
    let songs = ["Sunrise", "Kites", "Ocean", "Rain"];
    songs.push("Stars");
    show(songs.length);
33. 33.Which of these fits saving on the phone? (a) a shared to-do list (b) the sound on/off setting (c) chat messages to friends (d) a class leaderboard
34. 34.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
35. 35.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Aman", "Arjun", "Riya", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Arjun (c) Riya (d) Aman
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Zoya"];
    show(friends[2]); (a) Riya (b) Zoya (c) Arjun
37. 37.💾 What number does this code show?
    let notes = ["Art", "Maths"];
    notes.push("Science");
    notes.push("Music");
    show(notes.length);
38. 38.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
39. 39.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
40. 40.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Arjun", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Riya (d) Arjun

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