App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 107 · 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: notes to read offline fits saving in the cloud. (a) True (b) False
2. 2.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
3. 3.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) chat messages to friends (d) notes to read offline
4. 4.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a class leaderboard (d) your last game level
6. 6.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) notes to read offline (d) a class leaderboard
7. 7.💾 Which can hold many values in order? (a) a single number (b) a list (c) a switch (d) a button
8. 8.💾 What number does this code show?
   let songs = ["Stars", "Sunrise", "Kites", "Ocean"];
   songs.push("Monsoon");
   show(songs.length);
9. 9.💾 What number does this code show?
   let points = 4;
   points = points - 4;
   points = points + 4;
   show(points);
10. 10.💾 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
11. 11.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the app is closed (c) you send a message (d) the screen turns off
12. 12.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Art", "Hindi", "Music"];
    show(notes[4]); (a) Art (b) Music (c) Maths (d) Science
13. 13.💾 What number does this code show?
    let friends = ["Aman", "Zoya", "Kabir", "Riya"];
    friends.push("Arjun");
    friends.push("Meera");
    show(friends.length);
14. 14.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Art", "Maths", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Hindi (c) Art (d) Science
15. 15.💾 What number does this code show?
    let score = 5;
    score = score - 2;
    score = score + 1;
    show(score);
16. 16.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Rain", "Monsoon", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Stars (c) Monsoon (d) Rain
17. 17.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) chat messages to friends (d) a draft you are typing
18. 18.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
19. 19.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Monsoon", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Sunrise (c) Monsoon
20. 20.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
21. 21.💾 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
22. 22.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Science (c) Maths
23. 23.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
24. 24.💾 What number does this code show?
    let songs = ["Rain", "Kites"];
    songs.push("Monsoon");
    songs.push("Stars");
    show(songs.length);
25. 25.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Rain (c) Sunrise
26. 26.💾 What number does this code show?
    let lives = 8;
    lives = lives - 2;
    lives = lives + 4;
    show(lives);
27. 27.💾 What number does this code show?
    let lives = 8;
    lives = lives - 2;
    lives = lives + 1;
    show(lives);
28. 28.💾 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
29. 29.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) the sound on/off setting (d) a draft you are typing
30. 30.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
31. 31.True or false: your last game level fits saving in the cloud. (a) True (b) False
32. 32.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a type of screen (d) a picture
33. 33.💾 What number does this code show?
    let lives = 8;
    lives = lives - 1;
    lives = lives + 3;
    show(lives);
34. 34.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 1;
    show(score);
35. 35.💾 What number does this code show?
    let coins = 4;
    coins = coins - 2;
    coins = coins + 5;
    show(coins);
36. 36.💾 What number does this code show?
    let lives = 9;
    lives = lives - 6;
    lives = lives + 2;
    show(lives);
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Ocean", "Monsoon", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Kites (c) Monsoon (d) Sunrise
38. 38.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 2 (d) 1
39. 39.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) a class leaderboard (d) notes to read offline
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Meera", "Aman", "Zoya"];
    show(friends[1]); (a) Aman (b) Meera (c) Arjun (d) Zoya

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