App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 338 · 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.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) use it on any device (d) never need a password
2. 2.💾 pop() takes off the last item. What does this code show?
   let songs = ["Monsoon", "Kites", "Sunrise"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Monsoon (b) Sunrise (c) Kites
3. 3.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
4. 4.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) a class leaderboard (d) notes to read offline
6. 6.💾 What number does this code show?
   let friends = ["Meera", "Aman", "Riya"];
   friends.push("Arjun");
   show(friends.length);
7. 7.💾 pop() takes off the last item. What does this code show?
   let notes = ["Sports", "Music", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Art (c) Music
8. 8.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.💾 What number does this code show?
   let friends = ["Arjun", "Zoya", "Aman"];
   friends.push("Meera");
   friends.push("Kabir");
   show(friends.length);
10. 10.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
11. 11.True or false: your last game level fits saving in the cloud. (a) False (b) True
12. 12.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
13. 13.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
14. 14.💾 Which can hold many values in order? (a) a single number (b) a button (c) a switch (d) a list
15. 15.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the phone is lost (d) the screen turns off
16. 16.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Music", "Science", "Sports", "Hindi"];
    show(notes[2]); (a) Science (b) Music (c) Art (d) Sports
18. 18.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 1;
    show(points);
19. 19.Which of these fits saving on the phone? (a) your last game level (b) photos on two devices (c) chat messages to friends (d) a shared to-do list
20. 20.💾 What number does this code show?
    let notes = ["Maths", "Science"];
    notes.push("Music");
    notes.push("Art");
    show(notes.length);
21. 21.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
22. 22.💾 What number does this code show?
    let notes = ["Hindi", "Art"];
    notes.push("Sports");
    notes.push("Science");
    show(notes.length);
23. 23.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) photos on two devices (d) notes to read offline
24. 24.💾 What number does this code show?
    let notes = ["Art", "Maths", "Hindi", "Science"];
    notes.push("Music");
    notes.push("Sports");
    show(notes.length);
25. 25.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Stars", "Kites", "Ocean"];
    show(songs[1]); (a) Stars (b) Monsoon (c) Ocean (d) Kites
26. 26.Which of these fits saving in the cloud? (a) a draft you are typing (b) chat messages to friends (c) your last game level (d) the sound on/off setting
27. 27.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a shared to-do list (c) notes to read offline (d) your last game level
28. 28.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Kites", "Rain"];
    show(songs[1]); (a) Monsoon (b) Rain (c) Kites
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Science
30. 30.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
31. 31.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
32. 32.💾 What is a variable? (a) a type of screen (b) a named box for a value (c) a phone setting (d) a picture
33. 33.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) data saved on the phone (d) a shared chat
34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Sunrise (c) Stars
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Art", "Maths", "Music"];
    show(notes[3]); (a) Art (b) Science (c) Maths (d) Music
36. 36.💾 What number does this code show?
    let score = 6;
    score = score - 1;
    score = score + 4;
    show(score);
37. 37.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
39. 39.💾 What number does this code show?
    let coins = 7;
    coins = coins - 5;
    coins = coins + 3;
    show(coins);
40. 40.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) a draft you are typing

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