App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 844 · 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 can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
2. 2.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
3. 3.💾 What number does this code show?
   let notes = ["Science", "Music"];
   notes.push("Sports");
   show(notes.length);
4. 4.💾 What is a variable? (a) a named box for a value (b) a type of screen (c) a picture (d) a phone setting
5. 5.💾 pop() takes off the last item. What does this code show?
   let notes = ["Hindi", "Music", "Maths", "Sports"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Music (d) Maths
6. 6.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) chat messages to friends (d) notes to read offline
8. 8.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
9. 9.True or false: your last game level fits saving on the phone. (a) True (b) False
10. 10.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Maths
11. 11.💾 What number does this code show?
    let notes = ["Maths", "Music", "Art", "Hindi"];
    notes.push("Science");
    show(notes.length);
12. 12.💾 What number does this code show?
    let coins = 7;
    coins = coins - 6;
    coins = coins + 1;
    show(coins);
13. 13.💾 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
14. 14.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Riya", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Meera (c) Riya
15. 15.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
16. 16.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) chat messages to friends (d) your last game level
17. 17.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Meera"];
    show(friends[0]); (a) Kabir (b) Aman (c) Meera
18. 18.💾 What number does this code show?
    let coins = 6;
    coins = coins - 3;
    coins = coins + 2;
    show(coins);
19. 19.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) the sound on/off setting (d) a class leaderboard
20. 20.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
21. 21.💾 What number does this code show?
    let friends = ["Arjun", "Meera", "Aman"];
    friends.push("Riya");
    show(friends.length);
22. 22.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) you send a message (d) the phone is lost
23. 23.💾 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
24. 24.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
25. 25.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) a draft you are typing (d) chat messages to friends
26. 26.💾 What number does this code show?
    let songs = ["Stars", "Rain"];
    songs.push("Sunrise");
    show(songs.length);
27. 27.💾 What number does this code show?
    let coins = 5;
    coins = coins - 2;
    coins = coins + 3;
    show(coins);
28. 28.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) photos on two devices (d) a draft you are typing
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Music"];
    show(notes[1]); (a) Hindi (b) Music (c) Maths
30. 30.💾 What number does this code show?
    let friends = ["Kabir", "Meera"];
    friends.push("Arjun");
    show(friends.length);
31. 31.💾 What number does this code show?
    let friends = ["Kabir", "Riya", "Aman"];
    friends.push("Meera");
    friends.push("Zoya");
    show(friends.length);
32. 32.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Sports
33. 33.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) a class leaderboard (d) photos on two devices
34. 34.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) a shared to-do list
35. 35.True or false: notes to read offline fits saving on the phone. (a) True (b) False
36. 36.True or false: photos on two devices fits saving on the phone. (a) True (b) False
37. 37.💾 What number does this code show?
    let notes = ["Science", "Music", "Sports", "Maths"];
    notes.push("Art");
    notes.push("Hindi");
    show(notes.length);
38. 38.💾 What number does this code show?
    let lives = 4;
    lives = lives - 1;
    lives = lives + 5;
    show(lives);
39. 39.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Music", "Science"];
    show(notes[0]); (a) Music (b) Hindi (c) Science
40. 40.💾 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

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