App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 926 · 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.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 pop() takes off the last item. What does this code show?
   let songs = ["Rain", "Monsoon", "Stars", "Sunrise"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Stars (b) Monsoon (c) Sunrise (d) Rain
3. 3.True or false: your last game level fits saving in the cloud. (a) False (b) True
4. 4.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a named box for a value (d) a picture
5. 5.💾 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
6. 6.💾 pop() takes off the last item. What does this code show?
   let songs = ["Stars", "Rain", "Kites"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Rain
7. 7.💾 What number does this code show?
   let notes = ["Science", "Maths", "Art", "Hindi"];
   notes.push("Sports");
   notes.push("Music");
   show(notes.length);
8. 8.💾 What does this code show? (Positions start at 0.)
   let songs = ["Rain", "Sunrise", "Kites"];
   show(songs[0]); (a) Kites (b) Sunrise (c) Rain
9. 9.💾 pop() takes off the last item. What does this code show?
   let songs = ["Sunrise", "Stars", "Rain", "Ocean"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Ocean (b) Stars (c) Sunrise (d) Rain
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Monsoon", "Stars", "Rain", "Kites"];
    show(songs[0]); (a) Rain (b) Ocean (c) Monsoon (d) Stars
11. 11.💾 What number does this code show?
    let points = 8;
    points = points - 1;
    points = points + 5;
    show(points);
12. 12.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Kites", "Sunrise", "Stars"];
    show(songs[2]); (a) Monsoon (b) Kites (c) Rain (d) Sunrise
13. 13.💾 Which can hold many values in order? (a) a button (b) a switch (c) a list (d) a single number
14. 14.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
15. 15.💾 What number does this code show?
    let score = 6;
    score = score - 6;
    score = score + 3;
    show(score);
16. 16.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) chat messages to friends (d) notes to read offline
17. 17.💾 What number does this code show?
    let notes = ["Art", "Music"];
    notes.push("Sports");
    notes.push("Hindi");
    show(notes.length);
18. 18.💾 What number does this code show?
    let friends = ["Riya", "Arjun"];
    friends.push("Meera");
    show(friends.length);
19. 19.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
20. 20.💾 What number does this code show?
    let score = 4;
    score = score - 4;
    score = score + 1;
    show(score);
21. 21.Which of these fits saving on the phone? (a) the sound on/off setting (b) a shared to-do list (c) a class leaderboard (d) photos on two devices
22. 22.💾 What number does this code show?
    let coins = 5;
    coins = coins - 1;
    coins = coins + 1;
    show(coins);
23. 23.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
24. 24.💾 What number does this code show?
    let friends = ["Aman", "Zoya", "Kabir", "Meera"];
    friends.push("Riya");
    show(friends.length);
25. 25.💾 What number does this code show?
    let friends = ["Meera", "Riya", "Arjun", "Zoya"];
    friends.push("Aman");
    friends.push("Kabir");
    show(friends.length);
26. 26.Which of these fits saving on the phone? (a) notes to read offline (b) photos on two devices (c) a class leaderboard (d) chat messages to friends
27. 27.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) a shared to-do list (d) notes to read offline
28. 28.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Ocean", "Monsoon", "Sunrise", "Kites"];
    show(songs[4]); (a) Ocean (b) Kites (c) Monsoon (d) Rain
29. 29.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
30. 30.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
31. 31.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 3;
    show(lives);
32. 32.True or false: photos on two devices fits saving on the phone. (a) True (b) False
33. 33.💾 What number does this code show?
    let stars = 7;
    stars = stars - 6;
    stars = stars + 4;
    show(stars);
34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Sunrise", "Stars", "Monsoon", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Stars (c) Sunrise (d) Ocean
35. 35.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 2;
    show(score);
36. 36.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
37. 37.💾 What number does this code show?
    let songs = ["Ocean", "Sunrise", "Stars", "Kites"];
    songs.push("Rain");
    show(songs.length);
38. 38.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
39. 39.💾 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
40. 40.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) photos on two devices (d) the sound on/off setting

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