App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 585 · 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.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 What is a variable? (a) a phone setting (b) a type of screen (c) a picture (d) a named box for a value
3. 3.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) chat messages to friends (d) a draft you are typing
4. 4.💾 What number does this code show?
   let score = 6;
   score = score - 4;
   score = score + 3;
   show(score);
5. 5.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
6. 6.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) the sound on/off setting (d) a class leaderboard
7. 7.💾 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
8. 8.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Sports", "Maths", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Science (c) Hindi (d) Maths
9. 9.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Aman", "Zoya"];
   show(friends[1]); (a) Zoya (b) Aman (c) Riya
10. 10.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
11. 11.💾 What number does this code show?
    let friends = ["Aman", "Arjun", "Riya"];
    friends.push("Zoya");
    show(friends.length);
12. 12.💾 What number does this code show?
    let coins = 4;
    coins = coins - 2;
    coins = coins + 4;
    show(coins);
13. 13.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a button (d) a list
15. 15.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon", "Kites"];
    songs.push("Stars");
    show(songs.length);
16. 16.💾 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
17. 17.💾 What number does this code show?
    let songs = ["Monsoon", "Kites"];
    songs.push("Sunrise");
    show(songs.length);
18. 18.💾 What number does this code show?
    let coins = 8;
    coins = coins - 1;
    coins = coins + 2;
    show(coins);
19. 19.💾 What number does this code show?
    let songs = ["Ocean", "Sunrise", "Stars"];
    songs.push("Rain");
    songs.push("Kites");
    show(songs.length);
20. 20.💾 What number does this code show?
    let friends = ["Zoya", "Riya"];
    friends.push("Aman");
    show(friends.length);
21. 21.Which of these fits saving on the phone? (a) notes to read offline (b) a shared to-do list (c) chat messages to friends (d) a class leaderboard
22. 22.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
23. 23.💾 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
24. 24.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) chat messages to friends (d) a shared to-do list
25. 25.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Riya", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Zoya (c) Riya
26. 26.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
27. 27.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) never need a password (d) skip the internet
28. 28.💾 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
29. 29.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Zoya", "Meera"];
    show(friends[1]); (a) Zoya (b) Kabir (c) Meera
30. 30.💾 What number does this code show?
    let songs = ["Kites", "Rain", "Sunrise"];
    songs.push("Ocean");
    show(songs.length);
31. 31.💾 What number does this code show?
    let score = 8;
    score = score - 5;
    score = score + 4;
    show(score);
32. 32.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a cloud backup (c) data saved on the phone (d) a shared chat
33. 33.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
34. 34.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) photos on two devices (d) a draft you are typing
35. 35.💾 What number does this code show?
    let coins = 3;
    coins = coins - 2;
    coins = coins + 1;
    show(coins);
36. 36.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
37. 37.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Hindi", "Maths"];
    show(notes[1]); (a) Art (b) Hindi (c) Maths
38. 38.💾 What number does this code show?
    let notes = ["Hindi", "Science"];
    notes.push("Maths");
    show(notes.length);
39. 39.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
40. 40.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 10 (c) 2 (d) 0

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