App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 367 · 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 notes = ["Sports", "Science", "Maths", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Maths (d) Science
2. 2.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
3. 3.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 0 (d) 10
4. 4.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
5. 5.💾 What is a variable? (a) a type of screen (b) a picture (c) a named box for a value (d) a phone setting
6. 6.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) a shared to-do list (d) a draft you are typing
7. 7.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
8. 8.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) data saved on the phone (d) a cloud backup
9. 9.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) the sound on/off setting (d) a shared to-do list
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Ocean", "Monsoon"];
    show(songs[1]); (a) Kites (b) Sunrise (c) Ocean (d) Monsoon
11. 11.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
12. 12.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
13. 13.True or false: notes to read offline fits saving on the phone. (a) True (b) False
14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Monsoon", "Rain", "Ocean"];
    show(songs[3]); (a) Monsoon (b) Kites (c) Rain (d) Sunrise
15. 15.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Meera", "Zoya"];
    show(friends[2]); (a) Meera (b) Arjun (c) Zoya
16. 16.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Riya", "Kabir", "Zoya"];
    show(friends[0]); (a) Zoya (b) Meera (c) Riya (d) Kabir
17. 17.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
18. 18.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
19. 19.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a draft you are typing (d) a class leaderboard
20. 20.💾 What number does this code show?
    let lives = 4;
    lives = lives - 1;
    lives = lives + 3;
    show(lives);
21. 21.💾 What number does this code show?
    let notes = ["Maths", "Art"];
    notes.push("Hindi");
    notes.push("Science");
    show(notes.length);
22. 22.💾 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
23. 23.💾 What number does this code show?
    let score = 8;
    score = score - 1;
    score = score + 2;
    show(score);
24. 24.💾 What number does this code show?
    let songs = ["Ocean", "Rain", "Kites"];
    songs.push("Sunrise");
    songs.push("Stars");
    show(songs.length);
25. 25.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
26. 26.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
27. 27.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
28. 28.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
29. 29.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
30. 30.💾 What number does this code show?
    let notes = ["Maths", "Hindi"];
    notes.push("Science");
    show(notes.length);
31. 31.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Stars"];
    show(songs[1]); (a) Stars (b) Kites (c) Sunrise
32. 32.💾 What number does this code show?
    let songs = ["Sunrise", "Kites"];
    songs.push("Stars");
    show(songs.length);
33. 33.💾 What number does this code show?
    let lives = 9;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
34. 34.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
35. 35.Which of these fits saving on the phone? (a) photos on two devices (b) notes to read offline (c) a shared to-do list (d) a class leaderboard
36. 36.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
37. 37.💾 What number does this code show?
    let score = 6;
    score = score - 4;
    score = score + 3;
    show(score);
38. 38.💾 What number does this code show?
    let lives = 7;
    lives = lives - 5;
    lives = lives + 3;
    show(lives);
39. 39.💾 What number does this code show?
    let lives = 4;
    lives = lives - 4;
    lives = lives + 2;
    show(lives);
40. 40.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) the sound on/off setting (d) chat messages to friends

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