App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 341 · 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 songs = ["Monsoon", "Rain", "Kites", "Sunrise"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Rain (b) Sunrise (c) Kites (d) Monsoon
2. 2.💾 What number does this code show?
   let points = 3;
   points = points - 2;
   points = points + 3;
   show(points);
3. 3.💾 pop() takes off the last item. What does this code show?
   let songs = ["Kites", "Ocean", "Rain", "Sunrise", "Monsoon"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Rain (d) Kites
4. 4.💾 What number does this code show?
   let notes = ["Music", "Science", "Maths"];
   notes.push("Sports");
   notes.push("Art");
   show(notes.length);
5. 5.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) notes to read offline (d) chat messages to friends
6. 6.💾 What number does this code show?
   let coins = 9;
   coins = coins - 6;
   coins = coins + 1;
   show(coins);
7. 7.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
8. 8.💾 What number does this code show?
   let friends = ["Riya", "Arjun", "Meera", "Aman"];
   friends.push("Kabir");
   friends.push("Zoya");
   show(friends.length);
9. 9.💾 What number does this code show?
   let friends = ["Meera", "Kabir", "Zoya"];
   friends.push("Aman");
   friends.push("Riya");
   show(friends.length);
10. 10.💾 What number does this code show?
    let friends = ["Riya", "Zoya", "Meera", "Arjun"];
    friends.push("Aman");
    friends.push("Kabir");
    show(friends.length);
11. 11.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
12. 12.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
13. 13.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a picture (d) a named box for a value
14. 14.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
15. 15.Which of these fits saving in the cloud? (a) chat messages to friends (b) notes to read offline (c) your last game level (d) a draft you are typing
16. 16.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) use it on any device (d) never need a password
17. 17.True or false: your last game level fits saving on the phone. (a) True (b) False
18. 18.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
19. 19.💾 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
20. 20.True or false: your last game level fits saving in the cloud. (a) True (b) False
21. 21.💾 What number does this code show?
    let notes = ["Sports", "Music"];
    notes.push("Maths");
    show(notes.length);
22. 22.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Science", "Art", "Hindi"];
    show(notes[2]); (a) Music (b) Sports (c) Science (d) Art
23. 23.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
24. 24.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Rain", "Kites", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Rain (c) Kites (d) Stars
25. 25.💾 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
26. 26.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Arjun", "Riya"];
    show(friends[1]); (a) Riya (b) Arjun (c) Aman
27. 27.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 1 (d) 2
28. 28.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Kites", "Monsoon", "Rain", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Kites (c) Monsoon (d) Sunrise
29. 29.💾 What number does this code show?
    let songs = ["Kites", "Monsoon", "Rain", "Sunrise"];
    songs.push("Ocean");
    show(songs.length);
30. 30.💾 What number does this code show?
    let coins = 4;
    coins = coins - 2;
    coins = coins + 1;
    show(coins);
31. 31.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a class leaderboard (d) your last game level
32. 32.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Sports", "Science", "Music", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Science (c) Music (d) Sports
33. 33.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
34. 34.💾 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
35. 35.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
36. 36.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
37. 37.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a class leaderboard (d) a shared to-do list
38. 38.💾 What number does this code show?
    let friends = ["Riya", "Kabir"];
    friends.push("Arjun");
    show(friends.length);
39. 39.💾 What number does this code show?
    let notes = ["Music", "Science", "Maths"];
    notes.push("Sports");
    show(notes.length);
40. 40.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud

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