App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 678 · 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.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the phone is lost (c) you send a message (d) the screen turns off
2. 2.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a type of screen (d) a picture
3. 3.💾 What does this code show? (Positions start at 0.)
   let songs = ["Monsoon", "Kites", "Ocean"];
   show(songs[1]); (a) Ocean (b) Monsoon (c) Kites
4. 4.💾 What number does this code show?
   let lives = 7;
   lives = lives - 7;
   lives = lives + 3;
   show(lives);
5. 5.💾 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
6. 6.💾 What number does this code show?
   let score = 6;
   score = score - 6;
   score = score + 1;
   show(score);
7. 7.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 10 (c) 0 (d) 2
8. 8.Which of these fits saving in the cloud? (a) your last game level (b) chat messages to friends (c) a draft you are typing (d) notes to read offline
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Monsoon", "Rain", "Sunrise"];
   show(songs[2]); (a) Rain (b) Sunrise (c) Monsoon
10. 10.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
11. 11.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) a shared to-do list (d) notes to read offline
12. 12.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
13. 13.💾 What number does this code show?
    let friends = ["Aman", "Meera", "Kabir"];
    friends.push("Zoya");
    show(friends.length);
14. 14.💾 What number does this code show?
    let songs = ["Stars", "Rain"];
    songs.push("Sunrise");
    show(songs.length);
15. 15.💾 What number does this code show?
    let friends = ["Zoya", "Arjun", "Aman"];
    friends.push("Riya");
    show(friends.length);
16. 16.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
17. 17.💾 What number does this code show?
    let points = 5;
    points = points - 5;
    points = points + 1;
    show(points);
18. 18.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Riya", "Arjun", "Aman", "Zoya"];
    show(friends[4]); (a) Arjun (b) Zoya (c) Riya (d) Meera
19. 19.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Art (c) Hindi
20. 20.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a shared chat (d) a cloud backup
21. 21.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Monsoon (c) Sunrise
22. 22.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
23. 23.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
24. 24.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
25. 25.Which of these fits saving on the phone? (a) photos on two devices (b) notes to read offline (c) chat messages to friends (d) a shared to-do list
26. 26.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
27. 27.💾 What number does this code show?
    let notes = ["Music", "Science", "Art", "Hindi"];
    notes.push("Sports");
    show(notes.length);
28. 28.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Aman", "Kabir", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Kabir (c) Arjun (d) Aman
29. 29.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
30. 30.💾 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
31. 31.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon"];
    songs.push("Stars");
    songs.push("Kites");
    show(songs.length);
32. 32.True or false: your last game level fits saving in the cloud. (a) True (b) False
33. 33.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
34. 34.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) a class leaderboard (d) the sound on/off setting
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Sunrise (c) Monsoon
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Ocean", "Stars", "Rain", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Monsoon (c) Ocean (d) Stars
38. 38.💾 What number does this code show?
    let coins = 6;
    coins = coins - 1;
    coins = coins + 1;
    show(coins);
39. 39.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon", "Stars"];
    songs.push("Kites");
    songs.push("Ocean");
    show(songs.length);
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Kites", "Sunrise", "Ocean", "Stars"];
    show(songs[3]); (a) Kites (b) Ocean (c) Rain (d) Sunrise

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