App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 661 · 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.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Hindi", "Music"];
   show(notes[1]); (a) Sports (b) Hindi (c) Music
2. 2.💾 What number does this code show?
   let coins = 7;
   coins = coins - 1;
   coins = coins + 3;
   show(coins);
3. 3.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
4. 4.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
5. 5.Which of these fits saving in the cloud? (a) a shared to-do list (b) a draft you are typing (c) notes to read offline (d) your last game level
6. 6.💾 What number does this code show?
   let notes = ["Science", "Sports"];
   notes.push("Maths");
   show(notes.length);
7. 7.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 0 (d) 1
8. 8.Which of these fits saving on the phone? (a) a draft you are typing (b) a class leaderboard (c) photos on two devices (d) a shared to-do list
9. 9.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the screen turns off (c) the app is closed (d) you send a message
10. 10.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Arjun", "Kabir", "Riya", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Arjun (c) Riya (d) Zoya
11. 11.💾 What number does this code show?
    let score = 8;
    score = score - 4;
    score = score + 3;
    show(score);
12. 12.Which of these fits saving in the cloud? (a) your last game level (b) a class leaderboard (c) the sound on/off setting (d) a draft you are typing
13. 13.💾 What number does this code show?
    let friends = ["Riya", "Aman", "Meera"];
    friends.push("Kabir");
    friends.push("Arjun");
    show(friends.length);
14. 14.Which of these fits saving in the cloud? (a) a draft you are typing (b) chat messages to friends (c) notes to read offline (d) your last game level
15. 15.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon", "Kites", "Rain"];
    songs.push("Sunrise");
    songs.push("Stars");
    show(songs.length);
16. 16.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
17. 17.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
18. 18.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
19. 19.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) photos on two devices (d) a draft you are typing
20. 20.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
21. 21.Which of these fits saving on the phone? (a) a shared to-do list (b) the sound on/off setting (c) chat messages to friends (d) a class leaderboard
22. 22.💾 What number does this code show?
    let lives = 4;
    lives = lives - 1;
    lives = lives + 2;
    show(lives);
23. 23.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) shrink the app (c) never need a password (d) skip the internet
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Hindi", "Art", "Science", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Science (d) Hindi
25. 25.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
26. 26.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
27. 27.💾 What is a variable? (a) a type of screen (b) a picture (c) a named box for a value (d) a phone setting
28. 28.💾 What number does this code show?
    let coins = 4;
    coins = coins - 1;
    coins = coins + 3;
    show(coins);
29. 29.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) notes to read offline (d) photos on two devices
30. 30.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Art", "Hindi", "Maths"];
    show(notes[0]); (a) Sports (b) Art (c) Hindi (d) Music
31. 31.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Science", "Music"];
    show(notes[3]); (a) Hindi (b) Maths (c) Science (d) Music
32. 32.💾 What number does this code show?
    let lives = 3;
    lives = lives - 3;
    lives = lives + 1;
    show(lives);
33. 33.💾 What number does this code show?
    let songs = ["Rain", "Kites"];
    songs.push("Monsoon");
    songs.push("Ocean");
    show(songs.length);
34. 34.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
35. 35.💾 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
36. 36.💾 What number does this code show?
    let stars = 7;
    stars = stars - 2;
    stars = stars + 3;
    show(stars);
37. 37.💾 What number does this code show?
    let stars = 8;
    stars = stars - 8;
    stars = stars + 5;
    show(stars);
38. 38.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
39. 39.💾 What number does this code show?
    let notes = ["Hindi", "Art", "Maths", "Music"];
    notes.push("Science");
    show(notes.length);
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Ocean", "Rain", "Stars"];
    show(songs[1]); (a) Ocean (b) Rain (c) Sunrise (d) Kites

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