App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 692 · 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 friends = ["Arjun", "Kabir", "Aman", "Zoya", "Riya"];
   show(friends[3]); (a) Kabir (b) Arjun (c) Aman (d) Zoya
2. 2.💾 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
3. 3.💾 What number does this code show?
   let notes = ["Music", "Art"];
   notes.push("Sports");
   show(notes.length);
4. 4.💾 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
5. 5.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) the sound on/off setting (d) a class leaderboard
6. 6.💾 What number does this code show?
   let coins = 7;
   coins = coins - 4;
   coins = coins + 2;
   show(coins);
7. 7.💾 What number does this code show?
   let coins = 3;
   coins = coins - 1;
   coins = coins + 1;
   show(coins);
8. 8.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
9. 9.💾 pop() takes off the last item. What does this code show?
   let friends = ["Zoya", "Riya", "Kabir", "Meera"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Meera (b) Riya (c) Zoya (d) Kabir
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Monsoon", "Stars", "Kites"];
    show(songs[3]); (a) Stars (b) Rain (c) Monsoon (d) Kites
11. 11.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
12. 12.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) chat messages to friends (d) your last game level
13. 13.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Ocean", "Rain"];
    show(songs[2]); (a) Stars (b) Ocean (c) Rain
14. 14.💾 What number does this code show?
    let friends = ["Aman", "Kabir", "Zoya", "Riya"];
    friends.push("Meera");
    show(friends.length);
15. 15.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Riya", "Zoya", "Aman", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Zoya (c) Riya (d) Aman
17. 17.Which of these fits saving on the phone? (a) photos on two devices (b) the sound on/off setting (c) chat messages to friends (d) a shared to-do list
18. 18.💾 What number does this code show?
    let lives = 5;
    lives = lives - 2;
    lives = lives + 2;
    show(lives);
19. 19.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) a draft you are typing (d) a class leaderboard
20. 20.💾 What number does this code show?
    let songs = ["Kites", "Stars", "Ocean"];
    songs.push("Sunrise");
    show(songs.length);
21. 21.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a picture (d) a named box for a value
22. 22.True or false: your last game level fits saving in the cloud. (a) True (b) False
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Science", "Maths", "Music"];
    show(notes[2]); (a) Maths (b) Science (c) Sports (d) Art
24. 24.💾 Saving data in the cloud lets you ___. (a) never need a password (b) use it on any device (c) skip the internet (d) shrink the app
25. 25.💾 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
26. 26.True or false: photos on two devices fits saving on the phone. (a) False (b) True
27. 27.Which of these fits saving in the cloud? (a) a draft you are typing (b) a shared to-do list (c) the sound on/off setting (d) notes to read offline
28. 28.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Riya", "Aman", "Zoya", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Aman (c) Zoya (d) Kabir
29. 29.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) your last game level (d) photos on two devices
30. 30.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Stars", "Ocean", "Monsoon"];
    show(songs[0]); (a) Monsoon (b) Stars (c) Kites (d) Ocean
31. 31.💾 What number does this code show?
    let notes = ["Science", "Art", "Maths", "Music"];
    notes.push("Sports");
    show(notes.length);
32. 32.💾 What number does this code show?
    let stars = 8;
    stars = stars - 2;
    stars = stars + 1;
    show(stars);
33. 33.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Kabir", "Arjun"];
    show(friends[2]); (a) Riya (b) Kabir (c) Arjun
34. 34.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Rain", "Stars"];
    show(songs[3]); (a) Rain (b) Sunrise (c) Stars (d) Kites
35. 35.💾 What number does this code show?
    let score = 4;
    score = score - 1;
    score = score + 5;
    show(score);
36. 36.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
37. 37.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
38. 38.💾 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
39. 39.💾 What number does this code show?
    let coins = 6;
    coins = coins - 2;
    coins = coins + 4;
    show(coins);
40. 40.💾 What number does this code show?
    let points = 9;
    points = points - 8;
    points = points + 5;
    show(points);

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