App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 322 · 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) data saved on the phone (b) a shared chat (c) a cloud leaderboard (d) a cloud backup
2. 2.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) a shared to-do list (d) your last game level
3. 3.💾 What number does this code show?
   let friends = ["Kabir", "Meera"];
   friends.push("Aman");
   show(friends.length);
4. 4.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the phone is lost (d) the app is closed
5. 5.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
6. 6.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
7. 7.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Sunrise", "Kites"];
   show(songs[0]); (a) Kites (b) Sunrise (c) Stars
8. 8.💾 What is a variable? (a) a picture (b) a phone setting (c) a type of screen (d) a named box for a value
9. 9.💾 What number does this code show?
   let lives = 4;
   lives = lives - 4;
   lives = lives + 2;
   show(lives);
10. 10.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) never need a password (c) use it on any device (d) skip the internet
11. 11.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Ocean", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Ocean (c) Rain (d) Sunrise
12. 12.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Riya", "Kabir", "Aman", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Riya (c) Aman (d) Kabir
13. 13.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) your last game level (d) photos on two devices
14. 14.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) photos on two devices
15. 15.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Stars", "Monsoon", "Sunrise"];
    show(songs[2]); (a) Rain (b) Stars (c) Sunrise (d) Monsoon
16. 16.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
17. 17.True or false: your last game level fits saving in the cloud. (a) False (b) True
18. 18.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Sunrise", "Ocean", "Kites", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Sunrise (d) Ocean
19. 19.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Art", "Hindi", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Sports (d) Hindi
20. 20.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
21. 21.💾 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
22. 22.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Music", "Hindi", "Sports"];
    show(notes[0]); (a) Art (b) Sports (c) Hindi (d) Music
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Sports", "Maths", "Music", "Science"];
    show(notes[0]); (a) Maths (b) Art (c) Music (d) Sports
25. 25.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
26. 26.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) chat messages to friends (d) a draft you are typing
27. 27.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
28. 28.Which of these fits saving in the cloud? (a) a class leaderboard (b) the sound on/off setting (c) a draft you are typing (d) your last game level
29. 29.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Kabir"];
    show(friends[2]); (a) Meera (b) Kabir (c) Aman
30. 30.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
31. 31.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
32. 32.💾 What number does this code show?
    let coins = 5;
    coins = coins - 3;
    coins = coins + 2;
    show(coins);
33. 33.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 4;
    show(score);
34. 34.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 0 (d) 1
35. 35.💾 What number does this code show?
    let score = 7;
    score = score - 2;
    score = score + 1;
    show(score);
36. 36.💾 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
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Maths"];
    show(notes[1]); (a) Sports (b) Art (c) Maths
38. 38.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Art"];
    notes.push("Sports");
    show(notes.length);
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Art (c) Hindi (d) Maths
40. 40.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

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