App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 572 · 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.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
2. 2.💾 What number does this code show?
   let songs = ["Sunrise", "Kites", "Monsoon"];
   songs.push("Ocean");
   show(songs.length);
3. 3.Which of these fits saving in the cloud? (a) photos on two devices (b) the sound on/off setting (c) notes to read offline (d) your last game level
4. 4.True or false: your last game level fits saving in the cloud. (a) True (b) False
5. 5.💾 What number does this code show?
   let lives = 5;
   lives = lives - 3;
   lives = lives + 1;
   show(lives);
6. 6.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
7. 7.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
8. 8.💾 pop() takes off the last item. What does this code show?
   let notes = ["Hindi", "Music", "Maths"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Music
9. 9.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) shrink the app (c) use it on any device (d) never need a password
10. 10.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) the sound on/off setting (d) photos on two devices
11. 11.💾 What number does this code show?
    let friends = ["Meera", "Zoya"];
    friends.push("Kabir");
    show(friends.length);
12. 12.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.💾 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
14. 14.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
15. 15.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) your last game level
16. 16.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
17. 17.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Rain", "Monsoon", "Ocean"];
    show(songs[3]); (a) Rain (b) Ocean (c) Monsoon (d) Stars
18. 18.💾 Which can hold many values in order? (a) a button (b) a switch (c) a single number (d) a list
19. 19.Which of these fits saving in the cloud? (a) a shared to-do list (b) the sound on/off setting (c) your last game level (d) notes to read offline
20. 20.💾 What is a variable? (a) a phone setting (b) a picture (c) a named box for a value (d) a type of screen
21. 21.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Maths", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Music (d) Hindi
22. 22.💾 What number does this code show?
    let songs = ["Stars", "Ocean", "Kites"];
    songs.push("Rain");
    songs.push("Monsoon");
    show(songs.length);
23. 23.💾 What number does this code show?
    let coins = 4;
    coins = coins - 1;
    coins = coins + 1;
    show(coins);
24. 24.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
25. 25.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
26. 26.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a cloud backup (c) data saved on the phone (d) a shared chat
27. 27.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Science", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Science (c) Art (d) Sports
28. 28.💾 What number does this code show?
    let coins = 3;
    coins = coins - 1;
    coins = coins + 2;
    show(coins);
29. 29.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Kabir", "Meera", "Riya", "Zoya"];
    show(friends[3]); (a) Kabir (b) Riya (c) Meera (d) Arjun
30. 30.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) a class leaderboard (d) notes to read offline
31. 31.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Hindi", "Maths", "Art"];
    show(notes[2]); (a) Music (b) Science (c) Maths (d) Hindi
32. 32.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) a class leaderboard (d) notes to read offline
33. 33.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
34. 34.💾 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
35. 35.Which of these fits saving on the phone? (a) a draft you are typing (b) a shared to-do list (c) chat messages to friends (d) photos on two devices
36. 36.💾 What number does this code show?
    let songs = ["Kites", "Monsoon", "Rain"];
    songs.push("Ocean");
    show(songs.length);
37. 37.💾 What number does this code show?
    let points = 8;
    points = points - 1;
    points = points + 4;
    show(points);
38. 38.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Zoya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Meera (c) Aman
39. 39.💾 What number does this code show?
    let friends = ["Kabir", "Riya", "Aman", "Zoya"];
    friends.push("Arjun");
    friends.push("Meera");
    show(friends.length);
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Music

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