App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 188 · 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.💾 pop() takes off the last item. What does this code show?
   let songs = ["Ocean", "Sunrise", "Rain", "Monsoon"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Monsoon (b) Ocean (c) Rain (d) Sunrise
2. 2.💾 What number does this code show?
   let songs = ["Monsoon", "Sunrise", "Ocean"];
   songs.push("Rain");
   songs.push("Stars");
   show(songs.length);
3. 3.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) chat messages to friends (d) a class leaderboard
4. 4.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 0 (d) 10
5. 5.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
6. 6.💾 pop() takes off the last item. What does this code show?
   let notes = ["Maths", "Hindi", "Science", "Music", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Music (b) Hindi (c) Science (d) Maths
7. 7.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
8. 8.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) chat messages to friends (d) your last game level
9. 9.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud backup (d) a cloud leaderboard
10. 10.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the phone is lost (c) the screen turns off (d) you send a message
11. 11.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) photos on two devices (d) your last game level
12. 12.💾 What number does this code show?
    let points = 4;
    points = points - 2;
    points = points + 4;
    show(points);
13. 13.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) the sound on/off setting (d) a shared to-do list
14. 14.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Maths", "Art", "Sports"];
    show(notes[3]); (a) Maths (b) Music (c) Art (d) Sports
15. 15.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Stars", "Sunrise", "Monsoon"];
    show(songs[3]); (a) Monsoon (b) Stars (c) Sunrise (d) Kites
16. 16.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Science", "Music"];
    notes.push("Art");
    notes.push("Hindi");
    show(notes.length);
17. 17.💾 Which can hold many values in order? (a) a single number (b) a button (c) a switch (d) a list
18. 18.💾 What number does this code show?
    let coins = 5;
    coins = coins - 1;
    coins = coins + 5;
    show(coins);
19. 19.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.Which of these fits saving in the cloud? (a) chat messages to friends (b) your last game level (c) notes to read offline (d) the sound on/off setting
21. 21.💾 What number does this code show?
    let songs = ["Rain", "Sunrise", "Monsoon"];
    songs.push("Stars");
    show(songs.length);
22. 22.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Meera", "Riya"];
    show(friends[0]); (a) Kabir (b) Meera (c) Riya
23. 23.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
24. 24.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Stars", "Monsoon", "Sunrise"];
    show(songs[3]); (a) Rain (b) Sunrise (c) Stars (d) Monsoon
25. 25.💾 What number does this code show?
    let notes = ["Maths", "Music", "Sports", "Hindi"];
    notes.push("Science");
    show(notes.length);
26. 26.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Sports", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Sports (c) Maths (d) Art
27. 27.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Zoya", "Arjun", "Meera"];
    show(friends[4]); (a) Aman (b) Zoya (c) Meera (d) Riya
28. 28.💾 What number does this code show?
    let songs = ["Ocean", "Rain"];
    songs.push("Kites");
    songs.push("Sunrise");
    show(songs.length);
29. 29.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
30. 30.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) use it on any device (d) never need a password
31. 31.💾 What number does this code show?
    let stars = 7;
    stars = stars - 4;
    stars = stars + 3;
    show(stars);
32. 32.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
33. 33.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a class leaderboard (d) your last game level
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Meera", "Zoya", "Arjun"];
    show(friends[0]); (a) Riya (b) Meera (c) Arjun (d) Zoya
35. 35.True or false: photos on two devices fits saving on the phone. (a) False (b) True
36. 36.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a draft you are typing (d) a shared to-do list
37. 37.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Stars", "Ocean", "Sunrise"];
    show(songs[4]); (a) Sunrise (b) Monsoon (c) Stars (d) Rain
38. 38.💾 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
39. 39.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 shared to-do list
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Kites", "Sunrise", "Rain", "Stars"];
    show(songs[0]); (a) Sunrise (b) Kites (c) Rain (d) Monsoon

Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students