App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 875 · 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 friends = ["Aman", "Zoya", "Kabir", "Riya", "Meera"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Aman (b) Zoya (c) Riya (d) Kabir
2. 2.💾 Where should the app save chat messages to friends: 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) never need a password (b) shrink the app (c) skip the internet (d) use it on any device
4. 4.Which of these fits saving in the cloud? (a) a draft you are typing (b) a shared to-do list (c) notes to read offline (d) your last game level
5. 5.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) chat messages to friends (d) a draft you are typing
6. 6.💾 What number does this code show?
   let songs = ["Rain", "Kites", "Ocean", "Sunrise"];
   songs.push("Monsoon");
   show(songs.length);
7. 7.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
8. 8.💾 What does this code show? (Positions start at 0.)
   let notes = ["Hindi", "Art", "Science"];
   show(notes[0]); (a) Hindi (b) Art (c) Science
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Rain", "Kites", "Stars", "Monsoon", "Sunrise"];
   show(songs[0]); (a) Rain (b) Stars (c) Monsoon (d) Kites
10. 10.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 1;
    show(stars);
11. 11.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a class leaderboard (d) the sound on/off setting
12. 12.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) your last game level (d) photos on two devices
14. 14.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
15. 15.💾 What number does this code show?
    let friends = ["Riya", "Aman"];
    friends.push("Kabir");
    friends.push("Meera");
    show(friends.length);
16. 16.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 1 (c) 2 (d) 10
17. 17.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the phone is lost (d) the screen turns off
18. 18.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
19. 19.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) a draft you are typing
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Hindi", "Science"];
    show(notes[0]); (a) Hindi (b) Science (c) Sports
21. 21.💾 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
22. 22.💾 What is a variable? (a) a named box for a value (b) a picture (c) a phone setting (d) a type of screen
23. 23.True or false: your last game level fits saving on the phone. (a) True (b) False
24. 24.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
25. 25.Which of these fits saving on the phone? (a) notes to read offline (b) chat messages to friends (c) photos on two devices (d) a class leaderboard
26. 26.💾 What number does this code show?
    let songs = ["Monsoon", "Rain"];
    songs.push("Ocean");
    show(songs.length);
27. 27.💾 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
28. 28.💾 What number does this code show?
    let songs = ["Kites", "Rain", "Monsoon"];
    songs.push("Stars");
    songs.push("Ocean");
    show(songs.length);
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Sports", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Art
30. 30.💾 Which works with no internet at all? (a) a cloud backup (b) data saved on the phone (c) a shared chat (d) a cloud leaderboard
31. 31.💾 What number does this code show?
    let songs = ["Kites", "Rain", "Monsoon", "Ocean"];
    songs.push("Sunrise");
    show(songs.length);
32. 32.💾 What number does this code show?
    let notes = ["Sports", "Art"];
    notes.push("Hindi");
    notes.push("Music");
    show(notes.length);
33. 33.💾 What number does this code show?
    let notes = ["Art", "Maths", "Science", "Hindi"];
    notes.push("Music");
    show(notes.length);
34. 34.💾 What number does this code show?
    let friends = ["Riya", "Aman", "Zoya"];
    friends.push("Arjun");
    friends.push("Meera");
    show(friends.length);
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Aman", "Riya", "Arjun"];
    show(friends[2]); (a) Arjun (b) Riya (c) Aman (d) Zoya
36. 36.💾 What number does this code show?
    let friends = ["Arjun", "Zoya"];
    friends.push("Kabir");
    show(friends.length);
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Sports", "Hindi", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Music (d) Maths
38. 38.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
39. 39.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
40. 40.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone

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