App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 256 · 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 your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 What number does this code show?
   let points = 4;
   points = points - 2;
   points = points + 1;
   show(points);
3. 3.💾 What number does this code show?
   let notes = ["Sports", "Maths", "Science"];
   notes.push("Hindi");
   show(notes.length);
4. 4.💾 Which works with no internet at all? (a) a shared chat (b) a cloud leaderboard (c) a cloud backup (d) data saved on the phone
5. 5.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
6. 6.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
7. 7.💾 pop() takes off the last item. What does this code show?
   let songs = ["Sunrise", "Stars", "Ocean", "Monsoon", "Kites"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Stars (b) Monsoon (c) Ocean (d) Sunrise
8. 8.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
9. 9.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Sports", "Maths", "Science", "Music"];
   show(notes[0]); (a) Sports (b) Art (c) Science (d) Maths
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Ocean", "Stars", "Sunrise"];
    show(songs[4]); (a) Ocean (b) Rain (c) Sunrise (d) Kites
11. 11.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
12. 12.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Music", "Sports", "Maths"];
    show(notes[3]); (a) Music (b) Science (c) Sports (d) Art
13. 13.💾 What number does this code show?
    let stars = 9;
    stars = stars - 7;
    stars = stars + 1;
    show(stars);
14. 14.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Maths", "Sports", "Hindi"];
    show(notes[4]); (a) Maths (b) Art (c) Hindi (d) Science
15. 15.💾 What number does this code show?
    let points = 3;
    points = points - 1;
    points = points + 4;
    show(points);
16. 16.Which of these fits saving in the cloud? (a) notes to read offline (b) a class leaderboard (c) the sound on/off setting (d) your last game level
17. 17.💾 Which can hold many values in order? (a) a switch (b) a button (c) a single number (d) a list
18. 18.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
19. 19.💾 What number does this code show?
    let stars = 7;
    stars = stars - 1;
    stars = stars + 5;
    show(stars);
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Art", "Hindi", "Science"];
    show(notes[2]); (a) Science (b) Music (c) Hindi (d) Art
21. 21.💾 What number does this code show?
    let notes = ["Hindi", "Sports", "Science", "Art"];
    notes.push("Maths");
    show(notes.length);
22. 22.💾 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
23. 23.💾 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
24. 24.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) you send a message (c) the screen turns off (d) the app is closed
25. 25.💾 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
26. 26.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Sports"];
    show(notes[2]); (a) Sports (b) Science (c) Music
27. 27.Which of these fits saving on the phone? (a) chat messages to friends (b) the sound on/off setting (c) a shared to-do list (d) photos on two devices
28. 28.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Sunrise"];
    show(songs[0]); (a) Monsoon (b) Rain (c) Sunrise
29. 29.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) notes to read offline (d) chat messages to friends
30. 30.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
31. 31.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) chat messages to friends (d) notes to read offline
32. 32.💾 What number does this code show?
    let friends = ["Meera", "Riya"];
    friends.push("Zoya");
    show(friends.length);
33. 33.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
34. 34.💾 What number does this code show?
    let stars = 3;
    stars = stars - 3;
    stars = stars + 2;
    show(stars);
35. 35.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Zoya", "Riya", "Kabir", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Arjun (c) Kabir (d) Zoya
36. 36.True or false: notes to read offline fits saving on the phone. (a) True (b) False
37. 37.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Kabir", "Zoya", "Aman", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Riya (c) Aman (d) Kabir
38. 38.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Science
39. 39.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) shrink the app (c) never need a password (d) use it on any device
40. 40.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) the sound on/off setting (d) notes to read offline

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