App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 813 · 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 notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.💾 Which can hold many values in order? (a) a button (b) a list (c) a single number (d) a switch
4. 4.True or false: notes to read offline fits saving on the phone. (a) True (b) False
5. 5.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
6. 6.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
7. 7.💾 What number does this code show?
   let stars = 3;
   stars = stars - 1;
   stars = stars + 2;
   show(stars);
8. 8.💾 What number does this code show?
   let songs = ["Kites", "Sunrise", "Ocean", "Rain"];
   songs.push("Monsoon");
   songs.push("Stars");
   show(songs.length);
9. 9.💾 What number does this code show?
   let lives = 6;
   lives = lives - 1;
   lives = lives + 4;
   show(lives);
10. 10.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
11. 11.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Kabir"];
    show(friends[2]); (a) Aman (b) Riya (c) Kabir
12. 12.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a picture (d) a named box for a value
13. 13.💾 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
14. 14.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) you send a message (c) the phone is lost (d) the app is closed
15. 15.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) use it on any device (d) never need a password
16. 16.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Ocean", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Stars
17. 17.Which of these fits saving in the cloud? (a) a draft you are typing (b) photos on two devices (c) the sound on/off setting (d) notes to read offline
18. 18.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
19. 19.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Ocean", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Ocean (c) Monsoon
21. 21.💾 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
22. 22.💾 What number does this code show?
    let friends = ["Aman", "Arjun", "Riya"];
    friends.push("Meera");
    friends.push("Zoya");
    show(friends.length);
23. 23.💾 What number does this code show?
    let notes = ["Maths", "Music"];
    notes.push("Sports");
    notes.push("Science");
    show(notes.length);
24. 24.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a shared to-do list (d) a draft you are typing
25. 25.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 1;
    show(stars);
26. 26.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
27. 27.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Hindi", "Art"];
    show(notes[0]); (a) Hindi (b) Music (c) Art
28. 28.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Meera", "Arjun"];
    show(friends[1]); (a) Arjun (b) Meera (c) Kabir (d) Aman
29. 29.💾 What number does this code show?
    let songs = ["Rain", "Ocean", "Stars", "Kites"];
    songs.push("Sunrise");
    songs.push("Monsoon");
    show(songs.length);
30. 30.💾 What number does this code show?
    let lives = 5;
    lives = lives - 1;
    lives = lives + 4;
    show(lives);
31. 31.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
32. 32.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Music", "Sports", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Art (c) Hindi (d) Music
33. 33.Which of these fits saving on the phone? (a) notes to read offline (b) a class leaderboard (c) chat messages to friends (d) a shared to-do list
34. 34.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Music", "Maths"];
    show(notes[1]); (a) Science (b) Maths (c) Music (d) Art
35. 35.💾 What number does this code show?
    let score = 8;
    score = score - 5;
    score = score + 2;
    show(score);
36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Sports", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Science (c) Sports
37. 37.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
38. 38.💾 What number does this code show?
    let points = 7;
    points = points - 6;
    points = points + 3;
    show(points);
39. 39.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
40. 40.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 0 (c) 1 (d) 2

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