App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 794 · 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) chat messages to friends (b) a class leaderboard (c) your last game level (d) a shared to-do list
2. 2.💾 What does this code show? (Positions start at 0.)
   let friends = ["Aman", "Meera", "Zoya", "Kabir", "Arjun"];
   show(friends[2]); (a) Meera (b) Aman (c) Kabir (d) Zoya
3. 3.💾 What number does this code show?
   let songs = ["Rain", "Kites", "Monsoon"];
   songs.push("Ocean");
   show(songs.length);
4. 4.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
5. 5.💾 pop() takes off the last item. What does this code show?
   let notes = ["Hindi", "Maths", "Sports", "Music", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Music (d) Maths
6. 6.💾 What number does this code show?
   let points = 7;
   points = points - 2;
   points = points + 5;
   show(points);
7. 7.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) a class leaderboard (d) chat messages to friends
8. 8.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
9. 9.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
10. 10.💾 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
11. 11.Which of these fits saving on the phone? (a) the sound on/off setting (b) a shared to-do list (c) photos on two devices (d) chat messages to friends
12. 12.💾 What number does this code show?
    let stars = 9;
    stars = stars - 7;
    stars = stars + 4;
    show(stars);
13. 13.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Stars", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Stars (c) Rain
14. 14.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
15. 15.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) a draft you are typing (d) the sound on/off setting
16. 16.Which of these fits saving in the cloud? (a) notes to read offline (b) chat messages to friends (c) your last game level (d) a draft you are typing
17. 17.💾 What is a variable? (a) a picture (b) a phone setting (c) a type of screen (d) a named box for a value
18. 18.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Kites", "Ocean", "Sunrise", "Stars"];
    show(songs[3]); (a) Ocean (b) Monsoon (c) Kites (d) Sunrise
19. 19.💾 What number does this code show?
    let friends = ["Kabir", "Riya", "Arjun", "Zoya"];
    friends.push("Aman");
    show(friends.length);
20. 20.💾 What number does this code show?
    let songs = ["Ocean", "Kites", "Stars"];
    songs.push("Rain");
    songs.push("Monsoon");
    show(songs.length);
21. 21.Which of these fits saving on the phone? (a) a class leaderboard (b) a draft you are typing (c) a shared to-do list (d) photos on two devices
22. 22.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
23. 23.💾 What number does this code show?
    let notes = ["Maths", "Art"];
    notes.push("Hindi");
    notes.push("Science");
    show(notes.length);
24. 24.💾 Which works with no internet at all? (a) a shared chat (b) a cloud backup (c) a cloud leaderboard (d) data saved on the phone
25. 25.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Monsoon", "Kites"];
    show(songs[0]); (a) Monsoon (b) Kites (c) Stars
26. 26.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) your last game level (d) a class leaderboard
27. 27.💾 What number does this code show?
    let score = 4;
    score = score - 2;
    score = score + 2;
    show(score);
28. 28.💾 What number does this code show?
    let friends = ["Meera", "Arjun", "Zoya", "Riya"];
    friends.push("Aman");
    friends.push("Kabir");
    show(friends.length);
29. 29.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Arjun", "Aman"];
    show(friends[0]); (a) Kabir (b) Arjun (c) Aman
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Zoya", "Arjun", "Meera"];
    show(friends[0]); (a) Arjun (b) Zoya (c) Riya (d) Aman
31. 31.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Kites", "Monsoon", "Rain", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Rain (c) Ocean (d) Kites
32. 32.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Maths", "Art", "Sports", "Hindi"];
    show(notes[0]); (a) Maths (b) Science (c) Sports (d) Art
33. 33.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Arjun", "Aman", "Kabir", "Zoya"];
    show(friends[0]); (a) Arjun (b) Aman (c) Kabir (d) Meera
34. 34.💾 What number does this code show?
    let songs = ["Monsoon", "Stars", "Kites", "Sunrise"];
    songs.push("Rain");
    show(songs.length);
35. 35.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
36. 36.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) shrink the app (c) never need a password (d) skip the internet
37. 37.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Aman", "Riya", "Zoya", "Kabir"];
    show(friends[0]); (a) Arjun (b) Riya (c) Zoya (d) Aman
38. 38.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Stars", "Kites"];
    show(songs[2]); (a) Monsoon (b) Kites (c) Stars
39. 39.💾 Which can hold many values in order? (a) a button (b) a list (c) a single number (d) a switch
40. 40.True or false: your last game level fits saving on the phone. (a) True (b) False

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