App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 910 · 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 the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.💾 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
3. 3.💾 What number does this code show?
   let friends = ["Arjun", "Aman"];
   friends.push("Zoya");
   friends.push("Riya");
   show(friends.length);
4. 4.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) you send a message (c) the screen turns off (d) the app is closed
6. 6.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Hindi", "Music"];
   show(notes[2]); (a) Science (b) Hindi (c) Music
7. 7.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) shrink the app (d) use it on any device
8. 8.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Stars", "Monsoon"];
   show(songs[0]); (a) Kites (b) Monsoon (c) Stars
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Rain", "Stars", "Ocean"];
   show(songs[3]); (a) Kites (b) Stars (c) Rain (d) Ocean
10. 10.Which of these fits saving in the cloud? (a) photos on two devices (b) a draft you are typing (c) your last game level (d) notes to read offline
11. 11.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
12. 12.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
13. 13.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Art", "Sports"];
    show(notes[2]); (a) Sports (b) Hindi (c) Art
14. 14.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Kabir", "Zoya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Arjun (c) Aman (d) Kabir
15. 15.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) notes to read offline (d) chat messages to friends
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Meera", "Arjun", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Riya (c) Arjun (d) Zoya
17. 17.💾 What number does this code show?
    let coins = 9;
    coins = coins - 6;
    coins = coins + 3;
    show(coins);
18. 18.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
19. 19.💾 What number does this code show?
    let songs = ["Monsoon", "Stars"];
    songs.push("Ocean");
    songs.push("Sunrise");
    show(songs.length);
20. 20.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a type of screen (d) a picture
21. 21.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 5;
    show(points);
22. 22.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
23. 23.💾 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
24. 24.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 0 (c) 10 (d) 2
25. 25.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Aman", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Kabir (c) Zoya (d) Aman
26. 26.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
27. 27.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) the sound on/off setting (d) chat messages to friends
28. 28.💾 What number does this code show?
    let notes = ["Art", "Music"];
    notes.push("Sports");
    show(notes.length);
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Ocean", "Monsoon"];
    show(songs[0]); (a) Sunrise (b) Rain (c) Monsoon (d) Ocean
30. 30.💾 What number does this code show?
    let notes = ["Art", "Maths"];
    notes.push("Sports");
    notes.push("Music");
    show(notes.length);
31. 31.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 2;
    show(stars);
32. 32.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) a shared to-do list (d) the sound on/off setting
33. 33.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 3;
    show(points);
34. 34.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) a draft you are typing (d) a class leaderboard
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Maths", "Art"];
    show(notes[1]); (a) Sports (b) Art (c) Maths
36. 36.💾 Which can hold many values in order? (a) a button (b) a switch (c) a list (d) a single number
37. 37.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
38. 38.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) the sound on/off setting (d) a class leaderboard
39. 39.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
40. 40.💾 What number does this code show?
    let songs = ["Monsoon", "Kites"];
    songs.push("Stars");
    show(songs.length);

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