App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 942 · 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.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
2. 2.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
3. 3.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
4. 4.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Arjun", "Aman"];
   show(friends[1]); (a) Aman (b) Riya (c) Arjun
5. 5.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) the sound on/off setting (d) a class leaderboard
6. 6.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
7. 7.💾 What number does this code show?
   let stars = 5;
   stars = stars - 4;
   stars = stars + 1;
   show(stars);
8. 8.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
9. 9.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
10. 10.💾 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
11. 11.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
12. 12.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) photos on two devices (d) chat messages to friends
13. 13.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
14. 14.💾 What number does this code show?
    let friends = ["Arjun", "Aman"];
    friends.push("Kabir");
    show(friends.length);
15. 15.💾 What number does this code show?
    let points = 6;
    points = points - 1;
    points = points + 5;
    show(points);
16. 16.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Maths", "Science", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Sports (c) Hindi (d) Science
17. 17.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
18. 18.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
19. 19.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.Which of these fits saving in the cloud? (a) a shared to-do list (b) the sound on/off setting (c) your last game level (d) notes to read offline
21. 21.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
22. 22.💾 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
23. 23.💾 What number does this code show?
    let points = 5;
    points = points - 5;
    points = points + 2;
    show(points);
24. 24.💾 What number does this code show?
    let points = 3;
    points = points - 3;
    points = points + 2;
    show(points);
25. 25.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a named box for a value (d) a picture
26. 26.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Science"];
    notes.push("Sports");
    show(notes.length);
27. 27.💾 What number does this code show?
    let notes = ["Music", "Art"];
    notes.push("Science");
    show(notes.length);
28. 28.True or false: your last game level fits saving on the phone. (a) False (b) True
29. 29.💾 What number does this code show?
    let lives = 7;
    lives = lives - 3;
    lives = lives + 1;
    show(lives);
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Kabir", "Meera"];
    show(friends[0]); (a) Arjun (b) Kabir (c) Meera
31. 31.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
32. 32.💾 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
33. 33.💾 What number does this code show?
    let notes = ["Sports", "Art", "Science"];
    notes.push("Music");
    show(notes.length);
34. 34.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Ocean", "Kites"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
35. 35.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Kites", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Stars
37. 37.💾 What number does this code show?
    let notes = ["Hindi", "Art", "Maths"];
    notes.push("Music");
    notes.push("Science");
    show(notes.length);
38. 38.💾 What number does this code show?
    let lives = 9;
    lives = lives - 3;
    lives = lives + 5;
    show(lives);
39. 39.💾 What number does this code show?
    let friends = ["Kabir", "Meera", "Zoya", "Arjun"];
    friends.push("Aman");
    show(friends.length);
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Riya", "Zoya", "Kabir"];
    show(friends[3]); (a) Kabir (b) Riya (c) Zoya (d) Arjun

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