App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 848 · 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.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a picture (d) a type of screen
2. 2.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) never need a password (d) skip the internet
3. 3.💾 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
4. 4.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud backup (c) a shared chat (d) a cloud leaderboard
5. 5.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
6. 6.💾 pop() takes off the last item. What does this code show?
   let friends = ["Aman", "Zoya", "Meera", "Arjun"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Meera (b) Zoya (c) Aman (d) Arjun
7. 7.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Maths", "Science", "Hindi"];
   show(notes[2]); (a) Art (b) Hindi (c) Maths (d) Science
8. 8.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) a class leaderboard (d) notes to read offline
9. 9.💾 What number does this code show?
   let lives = 8;
   lives = lives - 7;
   lives = lives + 3;
   show(lives);
10. 10.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 1 (c) 10 (d) 0
11. 11.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
12. 12.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
13. 13.True or false: your last game level fits saving on the phone. (a) False (b) True
14. 14.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
15. 15.Which of these fits saving in the cloud? (a) your last game level (b) photos on two devices (c) a draft you are typing (d) the sound on/off setting
16. 16.💾 What number does this code show?
    let lives = 8;
    lives = lives - 2;
    lives = lives + 5;
    show(lives);
17. 17.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise", "Ocean"];
    songs.push("Kites");
    songs.push("Stars");
    show(songs.length);
18. 18.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Kites", "Sunrise", "Monsoon", "Rain"];
    show(songs[2]); (a) Kites (b) Monsoon (c) Stars (d) Sunrise
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Hindi", "Sports", "Science"];
    show(notes[0]); (a) Music (b) Science (c) Hindi (d) Sports
20. 20.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Zoya", "Meera", "Riya"];
    show(friends[2]); (a) Zoya (b) Riya (c) Kabir (d) Meera
21. 21.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Meera", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Kabir (c) Meera
22. 22.💾 What number does this code show?
    let friends = ["Arjun", "Meera", "Riya", "Zoya"];
    friends.push("Aman");
    friends.push("Kabir");
    show(friends.length);
23. 23.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a draft you are typing (d) photos on two devices
24. 24.Which of these fits saving on the phone? (a) photos on two devices (b) the sound on/off setting (c) a class leaderboard (d) a shared to-do list
25. 25.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
26. 26.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
27. 27.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
28. 28.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) your last game level (d) chat messages to friends
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Sunrise", "Ocean"];
    show(songs[1]); (a) Monsoon (b) Ocean (c) Sunrise
30. 30.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
31. 31.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Ocean", "Rain"];
    show(songs[0]); (a) Ocean (b) Kites (c) Rain
32. 32.💾 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
33. 33.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 3;
    show(points);
34. 34.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
36. 36.💾 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
37. 37.💾 What number does this code show?
    let points = 5;
    points = points - 4;
    points = points + 5;
    show(points);
38. 38.💾 What number does this code show?
    let songs = ["Rain", "Sunrise"];
    songs.push("Stars");
    show(songs.length);
39. 39.💾 What number does this code show?
    let points = 4;
    points = points - 2;
    points = points + 1;
    show(points);
40. 40.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Ocean"];
    songs.push("Kites");
    show(songs.length);

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