App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 443 · 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 number does this code show?
   let notes = ["Sports", "Art", "Science", "Maths"];
   notes.push("Hindi");
   show(notes.length);
2. 2.💾 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
3. 3.💾 What number does this code show?
   let notes = ["Hindi", "Music", "Sports", "Science"];
   notes.push("Maths");
   notes.push("Art");
   show(notes.length);
4. 4.💾 pop() takes off the last item. What does this code show?
   let songs = ["Stars", "Kites", "Ocean", "Sunrise"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Ocean (b) Kites (c) Stars (d) Sunrise
5. 5.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) shrink the app (c) skip the internet (d) never need a password
6. 6.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a draft you are typing (d) a shared to-do list
8. 8.💾 Which works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud backup (d) a cloud leaderboard
9. 9.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
10. 10.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) a class leaderboard (d) notes to read offline
11. 11.True or false: notes to read offline fits saving on the phone. (a) True (b) False
12. 12.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a named box for a value (d) a picture
13. 13.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Science"];
    show(notes[0]); (a) Sports (b) Art (c) Science
14. 14.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
15. 15.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a class leaderboard (d) chat messages to friends
16. 16.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
17. 17.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
18. 18.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Maths", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Art (d) Music
19. 19.💾 What number does this code show?
    let score = 5;
    score = score - 2;
    score = score + 2;
    show(score);
20. 20.True or false: your last game level fits saving in the cloud. (a) False (b) True
21. 21.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Riya", "Arjun"];
    show(friends[0]); (a) Aman (b) Arjun (c) Riya
22. 22.True or false: photos on two devices fits saving on the phone. (a) True (b) False
23. 23.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Riya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Aman (c) Riya
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Music", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Sports (c) Music (d) Art
25. 25.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
26. 26.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Stars", "Monsoon", "Rain"];
    show(songs[2]); (a) Ocean (b) Stars (c) Rain (d) Monsoon
27. 27.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
28. 28.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
29. 29.Which of these fits saving on the phone? (a) the sound on/off setting (b) photos on two devices (c) chat messages to friends (d) a shared to-do list
30. 30.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 4;
    show(score);
31. 31.💾 What number does this code show?
    let coins = 9;
    coins = coins - 7;
    coins = coins + 5;
    show(coins);
32. 32.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) the phone is lost (d) you send a message
33. 33.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Monsoon", "Sunrise"];
    show(songs[1]); (a) Monsoon (b) Kites (c) Sunrise
34. 34.💾 What number does this code show?
    let stars = 3;
    stars = stars - 3;
    stars = stars + 2;
    show(stars);
35. 35.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) your last game level (d) chat messages to friends
36. 36.💾 What number does this code show?
    let songs = ["Kites", "Rain"];
    songs.push("Monsoon");
    songs.push("Sunrise");
    show(songs.length);
37. 37.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Arjun", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Arjun (c) Aman
38. 38.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Science", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Sports (d) Science
39. 39.💾 What number does this code show?
    let notes = ["Hindi", "Music", "Sports"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
40. 40.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Zoya", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Riya (c) Zoya

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