App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 778 · 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 works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud backup (d) a cloud leaderboard
2. 2.💾 pop() takes off the last item. What does this code show?
   let friends = ["Kabir", "Zoya", "Arjun", "Riya", "Aman"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Kabir (b) Zoya (c) Riya (d) Arjun
3. 3.💾 What number does this code show?
   let friends = ["Zoya", "Riya"];
   friends.push("Meera");
   show(friends.length);
4. 4.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Music", "Hindi"];
   show(notes[0]); (a) Hindi (b) Sports (c) Music
5. 5.Which of these fits saving on the phone? (a) a class leaderboard (b) a draft you are typing (c) photos on two devices (d) chat messages to friends
6. 6.💾 What number does this code show?
   let notes = ["Music", "Hindi", "Art", "Maths"];
   notes.push("Sports");
   show(notes.length);
7. 7.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) a class leaderboard
8. 8.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) notes to read offline (d) a class leaderboard
9. 9.💾 What does this code show? (Positions start at 0.)
   let friends = ["Arjun", "Aman", "Meera", "Riya"];
   show(friends[1]); (a) Meera (b) Aman (c) Arjun (d) Riya
10. 10.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
11. 11.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Monsoon", "Sunrise"];
    show(songs[0]); (a) Monsoon (b) Sunrise (c) Rain
12. 12.💾 What number does this code show?
    let coins = 3;
    coins = coins - 3;
    coins = coins + 3;
    show(coins);
13. 13.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
14. 14.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
15. 15.💾 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
16. 16.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 3;
    show(stars);
17. 17.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) skip the internet (c) shrink the app (d) never need a password
18. 18.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
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 friends = ["Zoya", "Meera"];
    friends.push("Kabir");
    show(friends.length);
21. 21.Which of these fits saving in the cloud? (a) photos on two devices (b) the sound on/off setting (c) notes to read offline (d) your last game level
22. 22.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) the sound on/off setting (d) chat messages to friends
23. 23.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Ocean", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Stars (c) Rain
24. 24.True or false: photos on two devices fits saving on the phone. (a) False (b) True
25. 25.💾 What number does this code show?
    let notes = ["Maths", "Art", "Music", "Science"];
    notes.push("Hindi");
    notes.push("Sports");
    show(notes.length);
26. 26.💾 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
27. 27.💾 What number does this code show?
    let songs = ["Monsoon", "Sunrise", "Stars"];
    songs.push("Kites");
    songs.push("Ocean");
    show(songs.length);
28. 28.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) chat messages to friends (d) the sound on/off setting
29. 29.💾 What number does this code show?
    let lives = 4;
    lives = lives - 2;
    lives = lives + 4;
    show(lives);
30. 30.💾 What number does this code show?
    let coins = 7;
    coins = coins - 4;
    coins = coins + 3;
    show(coins);
31. 31.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) notes to read offline (d) a class leaderboard
32. 32.💾 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
33. 33.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Zoya"];
    show(friends[0]); (a) Kabir (b) Zoya (c) Aman
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Zoya", "Arjun"];
    show(friends[2]); (a) Aman (b) Zoya (c) Arjun
35. 35.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Music", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Maths (d) Music
36. 36.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
37. 37.True or false: notes to read offline fits saving on the phone. (a) True (b) False
38. 38.True or false: your last game level fits saving on the phone. (a) False (b) True
39. 39.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Riya", "Meera", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Kabir (c) Meera (d) Riya
40. 40.💾 What number does this code show?
    let lives = 8;
    lives = lives - 4;
    lives = lives + 4;
    show(lives);

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