App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 417 · 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.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) skip the internet (d) use it on any device
3. 3.💾 What does this code show? (Positions start at 0.)
   let songs = ["Rain", "Kites", "Ocean", "Sunrise", "Monsoon"];
   show(songs[3]); (a) Sunrise (b) Rain (c) Ocean (d) Kites
4. 4.💾 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
5. 5.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
6. 6.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) the sound on/off setting (d) a class leaderboard
7. 7.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
8. 8.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Hindi", "Music", "Science"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Music (c) Hindi (d) Science
9. 9.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
10. 10.💾 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
11. 11.Which of these fits saving in the cloud? (a) chat messages to friends (b) notes to read offline (c) a draft you are typing (d) the sound on/off setting
12. 12.True or false: photos on two devices fits saving on the phone. (a) True (b) False
13. 13.Which of these fits saving in the cloud? (a) your last game level (b) photos on two devices (c) notes to read offline (d) a draft you are typing
14. 14.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
15. 15.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
16. 16.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
17. 17.💾 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
18. 18.💾 What number does this code show?
    let score = 5;
    score = score - 2;
    score = score + 1;
    show(score);
19. 19.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Riya"];
    show(friends[0]); (a) Kabir (b) Aman (c) Riya
20. 20.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 5;
    show(score);
21. 21.💾 What number does this code show?
    let stars = 5;
    stars = stars - 3;
    stars = stars + 1;
    show(stars);
22. 22.💾 What number does this code show?
    let lives = 6;
    lives = lives - 4;
    lives = lives + 2;
    show(lives);
23. 23.💾 What number does this code show?
    let friends = ["Kabir", "Arjun", "Riya"];
    friends.push("Zoya");
    show(friends.length);
24. 24.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) your last game level (d) chat messages to friends
25. 25.💾 Which can hold many values in order? (a) a list (b) a button (c) a single number (d) a switch
26. 26.Which of these fits saving on the phone? (a) a draft you are typing (b) chat messages to friends (c) photos on two devices (d) a class leaderboard
27. 27.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Music", "Maths"];
    show(notes[0]); (a) Music (b) Science (c) Maths
28. 28.Which of these fits saving on the phone? (a) notes to read offline (b) a class leaderboard (c) photos on two devices (d) chat messages to friends
29. 29.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Monsoon", "Ocean", "Kites", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Kites (d) Monsoon
30. 30.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Monsoon", "Rain", "Sunrise", "Kites"];
    show(songs[2]); (a) Stars (b) Monsoon (c) Sunrise (d) Rain
31. 31.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Sports (c) Maths
32. 32.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.💾 What number does this code show?
    let songs = ["Rain", "Sunrise"];
    songs.push("Stars");
    songs.push("Monsoon");
    show(songs.length);
34. 34.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
35. 35.💾 What number does this code show?
    let notes = ["Sports", "Maths", "Science", "Music"];
    notes.push("Hindi");
    notes.push("Art");
    show(notes.length);
36. 36.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
37. 37.💾 What number does this code show?
    let points = 4;
    points = points - 4;
    points = points + 4;
    show(points);
38. 38.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a shared to-do list (c) notes to read offline (d) a draft you are typing
39. 39.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
40. 40.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud

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