App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 752 · 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.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) photos on two devices (d) chat messages to friends
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.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) a class leaderboard (d) a draft you are typing
4. 4.💾 What number does this code show?
   let lives = 3;
   lives = lives - 2;
   lives = lives + 3;
   show(lives);
5. 5.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) chat messages to friends (d) the sound on/off setting
6. 6.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) data saved on the phone (d) a cloud leaderboard
7. 7.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
8. 8.💾 What number does this code show?
   let songs = ["Ocean", "Monsoon", "Sunrise"];
   songs.push("Kites");
   songs.push("Rain");
   show(songs.length);
9. 9.True or false: your last game level fits saving in the cloud. (a) True (b) False
10. 10.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Kabir", "Meera", "Arjun", "Aman"];
    show(friends[2]); (a) Zoya (b) Arjun (c) Kabir (d) Meera
11. 11.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
12. 12.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) the sound on/off setting (d) a class leaderboard
13. 13.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 0 (c) 2 (d) 10
14. 14.True or false: notes to read offline fits saving on the phone. (a) True (b) False
15. 15.💾 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
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Aman", "Arjun", "Kabir", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Aman (c) Arjun (d) Zoya
17. 17.💾 What number does this code show?
    let friends = ["Riya", "Arjun", "Zoya", "Kabir"];
    friends.push("Aman");
    friends.push("Meera");
    show(friends.length);
18. 18.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
19. 19.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a picture (d) a named box for a value
20. 20.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
21. 21.💾 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
22. 22.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Kites", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Ocean
23. 23.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) you send a message (c) the screen turns off (d) the phone is lost
24. 24.💾 Which can hold many values in order? (a) a switch (b) a button (c) a single number (d) a list
25. 25.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Zoya"];
    show(friends[2]); (a) Zoya (b) Aman (c) Kabir
26. 26.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Arjun", "Meera"];
    show(friends[0]); (a) Arjun (b) Meera (c) Kabir
27. 27.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Monsoon", "Sunrise"];
    show(songs[1]); (a) Rain (b) Sunrise (c) Monsoon
28. 28.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Science
30. 30.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 1;
    show(score);
31. 31.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
32. 32.Which of these fits saving on the phone? (a) notes to read offline (b) photos on two devices (c) a class leaderboard (d) a shared to-do list
33. 33.💾 What number does this code show?
    let notes = ["Hindi", "Art"];
    notes.push("Music");
    show(notes.length);
34. 34.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) never need a password (c) use it on any device (d) skip the internet
35. 35.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) a draft you are typing (d) a shared to-do list
36. 36.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Sports", "Maths"];
    show(notes[0]); (a) Sports (b) Maths (c) Art
37. 37.💾 What number does this code show?
    let stars = 5;
    stars = stars - 4;
    stars = stars + 4;
    show(stars);
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Science", "Music"];
    show(notes[1]); (a) Sports (b) Science (c) Music
39. 39.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Sports", "Hindi", "Maths"];
    show(notes[1]); (a) Hindi (b) Sports (c) Art (d) Maths
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Stars", "Ocean"];
    show(songs[3]); (a) Kites (b) Rain (c) Ocean (d) Stars

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