App Dev Worksheet: Variables, Lists and Saving

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

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