App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 312 · 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.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) shrink the app (c) never need a password (d) use it on any device
2. 2.💾 pop() takes off the last item. What does this code show?
   let friends = ["Zoya", "Riya", "Meera", "Kabir", "Arjun"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Zoya (b) Riya (c) Kabir (d) Meera
3. 3.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Rain", "Kites", "Monsoon", "Sunrise"];
   show(songs[1]); (a) Rain (b) Stars (c) Kites (d) Monsoon
4. 4.True or false: photos on two devices fits saving on the phone. (a) True (b) False
5. 5.Which of these fits saving in the cloud? (a) chat messages to friends (b) notes to read offline (c) your last game level (d) the sound on/off setting
6. 6.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
7. 7.💾 What number does this code show?
   let songs = ["Ocean", "Stars"];
   songs.push("Kites");
   show(songs.length);
8. 8.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.💾 What number does this code show?
   let stars = 5;
   stars = stars - 3;
   stars = stars + 5;
   show(stars);
10. 10.💾 Which can hold many values in order? (a) a list (b) a button (c) a single number (d) a switch
11. 11.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
12. 12.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a cloud backup (c) a shared chat (d) data saved on the phone
13. 13.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Sports", "Hindi"];
    show(notes[0]); (a) Hindi (b) Art (c) Sports
15. 15.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Ocean", "Stars", "Rain"];
    show(songs[1]); (a) Sunrise (b) Rain (c) Stars (d) Ocean
16. 16.💾 What number does this code show?
    let lives = 4;
    lives = lives - 3;
    lives = lives + 2;
    show(lives);
17. 17.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) chat messages to friends (d) photos on two devices
18. 18.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Sunrise", "Ocean", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Monsoon (c) Ocean (d) Sunrise
19. 19.💾 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
20. 20.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
21. 21.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the app is closed (c) you send a message (d) the screen turns off
22. 22.💾 What number does this code show?
    let friends = ["Riya", "Aman", "Arjun"];
    friends.push("Meera");
    friends.push("Kabir");
    show(friends.length);
23. 23.💾 What number does this code show?
    let stars = 9;
    stars = stars - 3;
    stars = stars + 1;
    show(stars);
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Sports", "Art"];
    show(notes[0]); (a) Art (b) Sports (c) Music
25. 25.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
26. 26.💾 What number does this code show?
    let points = 7;
    points = points - 3;
    points = points + 5;
    show(points);
27. 27.True or false: notes to read offline fits saving on the phone. (a) False (b) True
28. 28.💾 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
29. 29.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
30. 30.💾 What number does this code show?
    let notes = ["Sports", "Maths", "Hindi"];
    notes.push("Science");
    show(notes.length);
31. 31.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Riya", "Zoya", "Meera", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Arjun (c) Riya (d) Zoya
32. 32.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Stars", "Rain", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Kites (d) Stars
33. 33.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) the sound on/off setting (d) chat messages to friends
34. 34.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
35. 35.True or false: your last game level fits saving on the phone. (a) False (b) True
36. 36.Which of these fits saving on the phone? (a) notes to read offline (b) a class leaderboard (c) chat messages to friends (d) a shared to-do list
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Maths", "Sports"];
    show(notes[0]); (a) Sports (b) Music (c) Maths
38. 38.True or false: your last game level fits saving in the cloud. (a) False (b) True
39. 39.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
40. 40.True or false: a shared to-do list fits saving on the phone. (a) False (b) True

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