App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 442 · 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 draft you are typing (b) a shared to-do list (c) chat messages to friends (d) a class leaderboard
2. 2.Which of these fits saving on the phone? (a) the sound on/off setting (b) a class leaderboard (c) chat messages to friends (d) a shared to-do list
3. 3.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud
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: chat messages to friends fits saving on the phone. (a) False (b) True
6. 6.💾 What number does this code show?
   let songs = ["Stars", "Sunrise"];
   songs.push("Ocean");
   show(songs.length);
7. 7.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) data saved on the phone (d) a cloud backup
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 does this code show? (Positions start at 0.)
   let songs = ["Ocean", "Kites", "Sunrise"];
   show(songs[2]); (a) Kites (b) Ocean (c) Sunrise
10. 10.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
11. 11.💾 What number does this code show?
    let notes = ["Art", "Science"];
    notes.push("Maths");
    show(notes.length);
12. 12.💾 What number does this code show?
    let songs = ["Rain", "Ocean", "Sunrise"];
    songs.push("Monsoon");
    show(songs.length);
13. 13.💾 What number does this code show?
    let points = 8;
    points = points - 3;
    points = points + 4;
    show(points);
14. 14.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
15. 15.💾 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
16. 16.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Sports", "Hindi", "Music", "Art"];
    show(notes[2]); (a) Music (b) Sports (c) Hindi (d) Science
17. 17.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Sunrise (c) Monsoon
18. 18.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
19. 19.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) photos on two devices (d) your last game level
20. 20.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Kabir"];
    show(friends[0]); (a) Aman (b) Riya (c) Kabir
21. 21.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
22. 22.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
23. 23.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
24. 24.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Kabir", "Zoya", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Arjun (c) Kabir (d) Meera
25. 25.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
26. 26.💾 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
27. 27.💾 Which can hold many values in order? (a) a button (b) a switch (c) a single number (d) a list
28. 28.💾 What number does this code show?
    let lives = 6;
    lives = lives - 4;
    lives = lives + 3;
    show(lives);
29. 29.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 0 (c) 1 (d) 2
30. 30.💾 What number does this code show?
    let notes = ["Hindi", "Maths"];
    notes.push("Science");
    notes.push("Art");
    show(notes.length);
31. 31.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 5;
    show(coins);
32. 32.💾 What number does this code show?
    let songs = ["Ocean", "Rain", "Sunrise"];
    songs.push("Kites");
    show(songs.length);
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Sports", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Science (c) Music (d) Hindi
34. 34.True or false: your last game level fits saving in the cloud. (a) True (b) False
35. 35.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
36. 36.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) notes to read offline (d) a class leaderboard
37. 37.True or false: notes to read offline fits saving on the phone. (a) False (b) True
38. 38.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) shrink the app (c) use it on any device (d) never need a password
39. 39.True or false: photos on two devices fits saving on the phone. (a) False (b) True
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Maths (c) Art

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