App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 551 · 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 = ["Art", "Science", "Hindi"];
   show(notes[0]); (a) Science (b) Hindi (c) Art
2. 2.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) never need a password (c) shrink the app (d) use it on any device
4. 4.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
5. 5.Which of these fits saving in the cloud? (a) chat messages to friends (b) a draft you are typing (c) your last game level (d) the sound on/off setting
6. 6.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) a class leaderboard (d) the sound on/off setting
7. 7.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
8. 8.💾 What number does this code show?
   let points = 7;
   points = points - 5;
   points = points + 4;
   show(points);
9. 9.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Ocean", "Sunrise", "Kites"];
    show(songs[3]); (a) Monsoon (b) Ocean (c) Sunrise (d) Rain
11. 11.💾 What number does this code show?
    let stars = 8;
    stars = stars - 2;
    stars = stars + 1;
    show(stars);
12. 12.💾 What number does this code show?
    let notes = ["Music", "Science", "Maths"];
    notes.push("Hindi");
    show(notes.length);
13. 13.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
14. 14.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting
15. 15.💾 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
16. 16.True or false: your last game level fits saving in the cloud. (a) True (b) False
17. 17.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Sunrise", "Monsoon", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Monsoon (c) Rain (d) Sunrise
18. 18.💾 What number does this code show?
    let notes = ["Science", "Music", "Maths", "Sports"];
    notes.push("Art");
    notes.push("Hindi");
    show(notes.length);
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Hindi", "Science"];
    show(notes[1]); (a) Hindi (b) Sports (c) Science
20. 20.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
21. 21.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean", "Rain", "Stars"];
    songs.push("Monsoon");
    show(songs.length);
22. 22.💾 What number does this code show?
    let songs = ["Rain", "Monsoon"];
    songs.push("Kites");
    songs.push("Ocean");
    show(songs.length);
23. 23.💾 What number does this code show?
    let songs = ["Rain", "Ocean", "Monsoon"];
    songs.push("Sunrise");
    show(songs.length);
24. 24.Which of these fits saving on the phone? (a) notes to read offline (b) chat messages to friends (c) a shared to-do list (d) a class leaderboard
25. 25.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Zoya", "Meera"];
    show(friends[2]); (a) Zoya (b) Meera (c) Aman (d) Kabir
26. 26.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
27. 27.💾 What number does this code show?
    let score = 6;
    score = score - 3;
    score = score + 4;
    show(score);
28. 28.💾 What number does this code show?
    let songs = ["Sunrise", "Stars", "Ocean", "Monsoon"];
    songs.push("Rain");
    show(songs.length);
29. 29.💾 What number does this code show?
    let notes = ["Art", "Music"];
    notes.push("Hindi");
    show(notes.length);
30. 30.True or false: notes to read offline fits saving on the phone. (a) False (b) True
31. 31.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the phone is lost (c) the app is closed (d) you send a message
32. 32.💾 What number does this code show?
    let score = 9;
    score = score - 8;
    score = score + 2;
    show(score);
33. 33.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
34. 34.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a cloud backup (d) a shared chat
35. 35.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a shared to-do list (d) the sound on/off setting
36. 36.💾 Which can hold many values in order? (a) a list (b) a single number (c) a switch (d) a button
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Hindi", "Music"];
    show(notes[2]); (a) Hindi (b) Science (c) Music
38. 38.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
39. 39.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Aman", "Kabir", "Meera"];
    show(friends[3]); (a) Kabir (b) Arjun (c) Riya (d) Aman
40. 40.💾 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

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