App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 592 · 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.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) your last game level (d) a shared to-do list
2. 2.💾 What does this code show? (Positions start at 0.)
   let friends = ["Zoya", "Riya", "Kabir"];
   show(friends[2]); (a) Kabir (b) Riya (c) Zoya
3. 3.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
4. 4.💾 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
5. 5.💾 What number does this code show?
   let notes = ["Art", "Hindi", "Maths", "Science"];
   notes.push("Sports");
   notes.push("Music");
   show(notes.length);
6. 6.💾 What number does this code show?
   let notes = ["Science", "Hindi", "Art"];
   notes.push("Music");
   notes.push("Sports");
   show(notes.length);
7. 7.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a picture (d) a named box for a value
8. 8.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
9. 9.💾 What number does this code show?
   let coins = 6;
   coins = coins - 4;
   coins = coins + 5;
   show(coins);
10. 10.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) you send a message (c) the app is closed (d) the screen turns off
11. 11.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
12. 12.💾 What number does this code show?
    let lives = 5;
    lives = lives - 4;
    lives = lives + 2;
    show(lives);
13. 13.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
14. 14.💾 Which can hold many values in order? (a) a list (b) a switch (c) a button (d) a single number
15. 15.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) your last game level
16. 16.💾 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
17. 17.True or false: notes to read offline fits saving on the phone. (a) False (b) True
18. 18.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) use it on any device (c) shrink the app (d) never need a password
19. 19.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
20. 20.💾 What number does this code show?
    let coins = 9;
    coins = coins - 3;
    coins = coins + 2;
    show(coins);
21. 21.True or false: your last game level fits saving on the phone. (a) False (b) True
22. 22.💾 What number does this code show?
    let notes = ["Art", "Sports", "Maths", "Music"];
    notes.push("Hindi");
    notes.push("Science");
    show(notes.length);
23. 23.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
24. 24.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
25. 25.💾 What number does this code show?
    let friends = ["Kabir", "Arjun", "Meera"];
    friends.push("Riya");
    friends.push("Aman");
    show(friends.length);
26. 26.💾 What number does this code show?
    let stars = 7;
    stars = stars - 4;
    stars = stars + 4;
    show(stars);
27. 27.💾 What number does this code show?
    let points = 7;
    points = points - 1;
    points = points + 1;
    show(points);
28. 28.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) photos on two devices (d) notes to read offline
29. 29.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
30. 30.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
31. 31.💾 What number does this code show?
    let songs = ["Kites", "Ocean", "Monsoon"];
    songs.push("Sunrise");
    show(songs.length);
32. 32.Which of these fits saving in the cloud? (a) notes to read offline (b) a class leaderboard (c) your last game level (d) the sound on/off setting
33. 33.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) your last game level (d) chat messages to friends
34. 34.💾 Which works with no internet at all? (a) a cloud backup (b) data saved on the phone (c) a cloud leaderboard (d) a shared chat
35. 35.💾 What number does this code show?
    let friends = ["Meera", "Aman", "Riya", "Arjun"];
    friends.push("Zoya");
    friends.push("Kabir");
    show(friends.length);
36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Science", "Music", "Sports", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Hindi (d) Science
37. 37.💾 What number does this code show?
    let friends = ["Zoya", "Aman", "Arjun"];
    friends.push("Riya");
    friends.push("Kabir");
    show(friends.length);
38. 38.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Art", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Science (c) Art (d) Maths
39. 39.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Riya", "Zoya"];
    show(friends[2]); (a) Arjun (b) Riya (c) Zoya
40. 40.💾 What number does this code show?
    let stars = 6;
    stars = stars - 5;
    stars = stars + 1;
    show(stars);

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