App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 229 · 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 a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a draft you are typing (d) chat messages to friends
3. 3.💾 pop() takes off the last item. What does this code show?
   let songs = ["Stars", "Sunrise", "Kites", "Rain"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Sunrise (b) Rain (c) Stars (d) Kites
4. 4.💾 What number does this code show?
   let songs = ["Ocean", "Monsoon", "Rain"];
   songs.push("Sunrise");
   songs.push("Kites");
   show(songs.length);
5. 5.💾 pop() takes off the last item. What does this code show?
   let notes = ["Maths", "Science", "Music", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Music (b) Maths (c) Science (d) Hindi
6. 6.💾 What does this code show? (Positions start at 0.)
   let friends = ["Meera", "Riya", "Kabir"];
   show(friends[1]); (a) Meera (b) Riya (c) Kabir
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Maths", "Sports", "Music"];
   show(notes[1]); (a) Music (b) Maths (c) Sports
8. 8.💾 What number does this code show?
   let points = 6;
   points = points - 6;
   points = points + 5;
   show(points);
9. 9.💾 What is a variable? (a) a type of screen (b) a picture (c) a phone setting (d) a named box for a value
10. 10.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the phone is lost (d) the screen turns off
11. 11.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) photos on two devices
12. 12.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 3;
    show(score);
13. 13.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Music", "Science", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Science (c) Hindi (d) Music
14. 14.💾 Which works with no internet at all? (a) a shared chat (b) a cloud leaderboard (c) data saved on the phone (d) a cloud backup
15. 15.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Sports", "Science", "Art", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Science (c) Hindi (d) Sports
16. 16.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
17. 17.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
18. 18.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Stars", "Ocean", "Rain", "Monsoon"];
    show(songs[0]); (a) Kites (b) Rain (c) Stars (d) Ocean
19. 19.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) photos on two devices (d) the sound on/off setting
20. 20.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Monsoon", "Ocean", "Kites", "Rain"];
    show(songs[0]); (a) Kites (b) Monsoon (c) Ocean (d) Stars
21. 21.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
22. 22.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Maths (c) Sports
23. 23.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
24. 24.💾 What number does this code show?
    let notes = ["Art", "Music"];
    notes.push("Sports");
    show(notes.length);
25. 25.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Sunrise", "Stars", "Ocean", "Rain"];
    show(songs[0]); (a) Monsoon (b) Sunrise (c) Ocean (d) Stars
26. 26.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Art"];
    show(notes[2]); (a) Science (b) Music (c) Art
27. 27.True or false: photos on two devices fits saving on the phone. (a) True (b) False
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Maths", "Art"];
    show(notes[1]); (a) Science (b) Music (c) Maths (d) Art
29. 29.💾 What number does this code show?
    let songs = ["Ocean", "Kites", "Sunrise"];
    songs.push("Rain");
    show(songs.length);
30. 30.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
31. 31.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
32. 32.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Maths"];
    show(notes[0]); (a) Sports (b) Art (c) Maths
33. 33.💾 Which can hold many values in order? (a) a list (b) a switch (c) a button (d) a single number
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Zoya", "Riya", "Kabir"];
    show(friends[3]); (a) Meera (b) Aman (c) Riya (d) Zoya
35. 35.💾 What number does this code show?
    let friends = ["Meera", "Riya", "Aman"];
    friends.push("Zoya");
    show(friends.length);
36. 36.💾 What number does this code show?
    let songs = ["Monsoon", "Kites"];
    songs.push("Stars");
    show(songs.length);
37. 37.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) your last game level (d) a class leaderboard
38. 38.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon", "Rain", "Kites"];
    songs.push("Sunrise");
    show(songs.length);
39. 39.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
40. 40.💾 What number does this code show?
    let coins = 5;
    coins = coins - 3;
    coins = coins + 2;
    show(coins);

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