App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 307 · 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 in the cloud? (a) your last game level (b) a shared to-do list (c) notes to read offline (d) the sound on/off setting
2. 2.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud leaderboard (d) a cloud backup
3. 3.💾 What number does this code show?
   let notes = ["Maths", "Science"];
   notes.push("Hindi");
   show(notes.length);
4. 4.💾 What number does this code show?
   let notes = ["Maths", "Hindi", "Sports"];
   notes.push("Science");
   show(notes.length);
5. 5.💾 What number does this code show?
   let friends = ["Meera", "Zoya", "Aman"];
   friends.push("Riya");
   friends.push("Arjun");
   show(friends.length);
6. 6.Which of these fits saving on the phone? (a) a draft you are typing (b) a class leaderboard (c) photos on two devices (d) a shared to-do list
7. 7.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a type of screen (d) a picture
8. 8.💾 Saving data in the cloud lets you ___. (a) never need a password (b) use it on any device (c) shrink the app (d) skip the internet
9. 9.💾 pop() takes off the last item. What does this code show?
   let friends = ["Arjun", "Zoya", "Aman"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Zoya (b) Aman (c) Arjun
10. 10.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
11. 11.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 1;
    show(stars);
12. 12.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Hindi", "Maths", "Music"];
    show(notes[0]); (a) Hindi (b) Science (c) Music (d) Maths
13. 13.Which of these fits saving in the cloud? (a) photos on two devices (b) notes to read offline (c) the sound on/off setting (d) a draft you are typing
14. 14.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) chat messages to friends (d) notes to read offline
15. 15.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 1 (d) 10
16. 16.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) photos on two devices (d) chat messages to friends
17. 17.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Sunrise", "Ocean", "Rain"];
    show(songs[3]); (a) Stars (b) Rain (c) Ocean (d) Sunrise
18. 18.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Meera", "Arjun", "Riya", "Aman"];
    show(friends[1]); (a) Zoya (b) Meera (c) Arjun (d) Riya
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Hindi", "Sports", "Science"];
    show(notes[0]); (a) Science (b) Hindi (c) Art (d) Sports
20. 20.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
21. 21.💾 What number does this code show?
    let notes = ["Maths", "Music", "Science", "Art"];
    notes.push("Hindi");
    notes.push("Sports");
    show(notes.length);
22. 22.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
23. 23.Which of these fits saving on the phone? (a) chat messages to friends (b) the sound on/off setting (c) a shared to-do list (d) a class leaderboard
24. 24.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Kabir", "Zoya", "Aman"];
    show(friends[0]); (a) Aman (b) Zoya (c) Arjun (d) Kabir
25. 25.💾 What number does this code show?
    let friends = ["Zoya", "Aman", "Meera"];
    friends.push("Riya");
    friends.push("Arjun");
    show(friends.length);
26. 26.True or false: your last game level fits saving on the phone. (a) False (b) True
27. 27.💾 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
28. 28.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
29. 29.💾 What number does this code show?
    let friends = ["Riya", "Meera", "Aman", "Kabir"];
    friends.push("Arjun");
    show(friends.length);
30. 30.True or false: photos on two devices fits saving on the phone. (a) True (b) False
31. 31.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
32. 32.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise", "Rain", "Stars"];
    songs.push("Ocean");
    songs.push("Kites");
    show(songs.length);
33. 33.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
34. 34.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Zoya", "Meera", "Aman"];
    show(friends[2]); (a) Zoya (b) Meera (c) Aman (d) Kabir
36. 36.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
37. 37.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Ocean", "Kites"];
    show(songs[0]); (a) Kites (b) Ocean (c) Stars
38. 38.💾 What number does this code show?
    let songs = ["Ocean", "Rain"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
39. 39.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 2;
    show(points);
40. 40.💾 What number does this code show?
    let songs = ["Ocean", "Rain", "Sunrise"];
    songs.push("Monsoon");
    songs.push("Kites");
    show(songs.length);

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