App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 885 · 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 friends = ["Riya", "Arjun", "Zoya"];
   show(friends[2]); (a) Riya (b) Zoya (c) Arjun
2. 2.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
3. 3.Which of these fits saving on the phone? (a) a class leaderboard (b) a draft you are typing (c) photos on two devices (d) a shared to-do list
4. 4.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Sports", "Music", "Hindi"];
   show(notes[0]); (a) Sports (b) Science (c) Music (d) Hindi
5. 5.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
6. 6.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Maths", "Art"];
   show(notes[0]); (a) Art (b) Maths (c) Science
7. 7.💾 What does this code show? (Positions start at 0.)
   let songs = ["Rain", "Sunrise", "Ocean", "Kites", "Monsoon"];
   show(songs[2]); (a) Rain (b) Sunrise (c) Kites (d) Ocean
8. 8.💾 What number does this code show?
   let songs = ["Rain", "Monsoon"];
   songs.push("Ocean");
   show(songs.length);
9. 9.💾 pop() takes off the last item. What does this code show?
   let friends = ["Arjun", "Riya", "Aman"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Riya (b) Arjun (c) Aman
10. 10.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Aman", "Riya", "Arjun", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Aman (c) Meera (d) Arjun
11. 11.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Zoya", "Aman", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Meera (c) Zoya (d) Aman
12. 12.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
13. 13.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
14. 14.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
15. 15.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 10 (c) 0 (d) 2
16. 16.True or false: your last game level fits saving in the cloud. (a) True (b) False
17. 17.💾 What number does this code show?
    let notes = ["Maths", "Art", "Music"];
    notes.push("Science");
    notes.push("Hindi");
    show(notes.length);
18. 18.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Sunrise (c) Monsoon
19. 19.True or false: your last game level fits saving on the phone. (a) True (b) False
20. 20.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Monsoon"];
    show(songs[1]); (a) Kites (b) Monsoon (c) Rain
21. 21.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the screen turns off (d) the phone is lost
22. 22.💾 What number does this code show?
    let songs = ["Kites", "Monsoon"];
    songs.push("Sunrise");
    songs.push("Stars");
    show(songs.length);
23. 23.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) chat messages to friends (d) notes to read offline
24. 24.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Meera", "Aman"];
    show(friends[0]); (a) Riya (b) Meera (c) Aman
25. 25.Which of these fits saving in the cloud? (a) a shared to-do list (b) notes to read offline (c) the sound on/off setting (d) your last game level
26. 26.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) use it on any device (d) shrink the app
27. 27.💾 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
28. 28.💾 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
29. 29.True or false: notes to read offline fits saving on the phone. (a) True (b) False
30. 30.💾 What number does this code show?
    let notes = ["Sports", "Maths"];
    notes.push("Science");
    notes.push("Art");
    show(notes.length);
31. 31.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Meera", "Arjun", "Kabir"];
    show(friends[3]); (a) Kabir (b) Meera (c) Aman (d) Arjun
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Sunrise", "Rain"];
    show(songs[2]); (a) Sunrise (b) Rain (c) Stars
33. 33.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
34. 34.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
35. 35.💾 What number does this code show?
    let lives = 8;
    lives = lives - 8;
    lives = lives + 4;
    show(lives);
36. 36.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) chat messages to friends (d) the sound on/off setting
37. 37.💾 What number does this code show?
    let notes = ["Science", "Art"];
    notes.push("Music");
    show(notes.length);
38. 38.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Riya", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Meera (c) Riya
39. 39.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 2;
    show(points);
40. 40.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a class leaderboard (d) the sound on/off setting

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