App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 837 · 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 number does this code show?
   let songs = ["Rain", "Sunrise"];
   songs.push("Kites");
   show(songs.length);
2. 2.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) notes to read offline (d) a shared to-do list
3. 3.💾 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
4. 4.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
6. 6.💾 What does this code show? (Positions start at 0.)
   let notes = ["Science", "Maths", "Art", "Sports", "Hindi"];
   show(notes[3]); (a) Science (b) Art (c) Maths (d) Sports
7. 7.💾 What number does this code show?
   let score = 3;
   score = score - 1;
   score = score + 3;
   show(score);
8. 8.True or false: notes to read offline fits saving on the phone. (a) False (b) True
9. 9.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) the sound on/off setting (d) chat messages to friends
10. 10.💾 What number does this code show?
    let friends = ["Riya", "Meera", "Zoya", "Arjun"];
    friends.push("Aman");
    friends.push("Kabir");
    show(friends.length);
11. 11.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
12. 12.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) the sound on/off setting (d) photos on two devices
13. 13.💾 What number does this code show?
    let lives = 8;
    lives = lives - 3;
    lives = lives + 1;
    show(lives);
14. 14.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Maths", "Music", "Science"];
    show(notes[2]); (a) Science (b) Sports (c) Maths (d) Music
15. 15.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
16. 16.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) photos on two devices
17. 17.💾 What number does this code show?
    let coins = 8;
    coins = coins - 6;
    coins = coins + 5;
    show(coins);
18. 18.True or false: photos on two devices fits saving on the phone. (a) True (b) False
19. 19.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
20. 20.💾 What number does this code show?
    let score = 6;
    score = score - 2;
    score = score + 4;
    show(score);
21. 21.💾 What number does this code show?
    let notes = ["Maths", "Sports"];
    notes.push("Science");
    notes.push("Art");
    show(notes.length);
22. 22.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Ocean", "Stars", "Monsoon", "Kites"];
    show(songs[0]); (a) Monsoon (b) Sunrise (c) Ocean (d) Stars
23. 23.💾 What is a variable? (a) a phone setting (b) a picture (c) a named box for a value (d) a type of screen
24. 24.💾 What number does this code show?
    let coins = 7;
    coins = coins - 5;
    coins = coins + 2;
    show(coins);
25. 25.Which of these fits saving in the cloud? (a) your last game level (b) a class leaderboard (c) a draft you are typing (d) notes to read offline
26. 26.💾 Which can hold many values in order? (a) a list (b) a single number (c) a switch (d) a button
27. 27.💾 What number does this code show?
    let notes = ["Science", "Sports", "Art", "Music"];
    notes.push("Hindi");
    notes.push("Maths");
    show(notes.length);
28. 28.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
29. 29.💾 What number does this code show?
    let songs = ["Kites", "Stars", "Rain", "Sunrise"];
    songs.push("Monsoon");
    songs.push("Ocean");
    show(songs.length);
30. 30.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
31. 31.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) photos on two devices (d) a shared to-do list
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Rain", "Kites"];
    show(songs[2]); (a) Rain (b) Stars (c) Kites
33. 33.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Sports", "Maths"];
    show(notes[2]); (a) Sports (b) Maths (c) Science
34. 34.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Art", "Music"];
    notes.push("Science");
    notes.push("Sports");
    show(notes.length);
35. 35.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean", "Kites"];
    songs.push("Rain");
    show(songs.length);
36. 36.💾 What number does this code show?
    let songs = ["Sunrise", "Kites", "Stars", "Ocean"];
    songs.push("Rain");
    show(songs.length);
37. 37.💾 What number does this code show?
    let notes = ["Maths", "Science", "Hindi"];
    notes.push("Music");
    notes.push("Sports");
    show(notes.length);
38. 38.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
39. 39.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
40. 40.💾 What number does this code show?
    let score = 8;
    score = score - 2;
    score = score + 1;
    show(score);

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