App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 951 · 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 of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) chat messages to friends (d) a draft you are typing
2. 2.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
3. 3.💾 What number does this code show?
   let notes = ["Hindi", "Art"];
   notes.push("Science");
   show(notes.length);
4. 4.💾 What number does this code show?
   let notes = ["Maths", "Science"];
   notes.push("Sports");
   show(notes.length);
5. 5.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
6. 6.💾 What number does this code show?
   let coins = 5;
   coins = coins - 4;
   coins = coins + 1;
   show(coins);
7. 7.💾 What number does this code show?
   let points = 5;
   points = points - 3;
   points = points + 5;
   show(points);
8. 8.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) your last game level (d) chat messages to friends
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Monsoon", "Stars", "Rain", "Sunrise"];
   show(songs[3]); (a) Monsoon (b) Kites (c) Stars (d) Rain
10. 10.💾 What number does this code show?
    let friends = ["Arjun", "Zoya"];
    friends.push("Kabir");
    friends.push("Meera");
    show(friends.length);
11. 11.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) your last game level (d) photos on two devices
12. 12.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
13. 13.💾 What number does this code show?
    let score = 5;
    score = score - 2;
    score = score + 3;
    show(score);
14. 14.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
15. 15.💾 What number does this code show?
    let friends = ["Zoya", "Riya", "Aman", "Kabir"];
    friends.push("Meera");
    friends.push("Arjun");
    show(friends.length);
16. 16.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
17. 17.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Sunrise", "Monsoon"];
    show(songs[1]); (a) Monsoon (b) Ocean (c) Sunrise
18. 18.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Rain", "Stars", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Sunrise (c) Monsoon (d) Stars
19. 19.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
20. 20.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) the sound on/off setting (d) chat messages to friends
21. 21.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 1;
    show(score);
22. 22.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
23. 23.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 0 (c) 10 (d) 2
24. 24.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) a class leaderboard (d) the sound on/off setting
25. 25.True or false: your last game level fits saving in the cloud. (a) True (b) False
26. 26.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a button (d) a list
27. 27.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) you send a message (c) the screen turns off (d) the app is closed
28. 28.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
29. 29.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 5;
    show(stars);
30. 30.💾 What number does this code show?
    let score = 4;
    score = score - 3;
    score = score + 2;
    show(score);
31. 31.💾 What number does this code show?
    let songs = ["Stars", "Rain"];
    songs.push("Monsoon");
    show(songs.length);
32. 32.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Riya", "Kabir", "Arjun", "Zoya"];
    show(friends[2]); (a) Meera (b) Riya (c) Kabir (d) Arjun
33. 33.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
34. 34.Which of these fits saving on the phone? (a) notes to read offline (b) a shared to-do list (c) chat messages to friends (d) photos on two devices
35. 35.💾 What number does this code show?
    let songs = ["Sunrise", "Monsoon"];
    songs.push("Ocean");
    show(songs.length);
36. 36.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
37. 37.💾 What number does this code show?
    let lives = 9;
    lives = lives - 8;
    lives = lives + 2;
    show(lives);
38. 38.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
39. 39.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
40. 40.True or false: photos on two devices fits saving on the phone. (a) True (b) False

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