App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 858 · 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 friends = ["Riya", "Kabir", "Aman"];
   friends.push("Zoya");
   friends.push("Meera");
   show(friends.length);
2. 2.💾 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
3. 3.Which of these fits saving in the cloud? (a) a class leaderboard (b) notes to read offline (c) your last game level (d) a draft you are typing
4. 4.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
5. 5.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
6. 6.💾 What number does this code show?
   let score = 9;
   score = score - 1;
   score = score + 2;
   show(score);
7. 7.💾 pop() takes off the last item. What does this code show?
   let notes = ["Maths", "Hindi", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Hindi (c) Art
8. 8.💾 What number does this code show?
   let stars = 9;
   stars = stars - 6;
   stars = stars + 1;
   show(stars);
9. 9.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
10. 10.💾 What number does this code show?
    let stars = 5;
    stars = stars - 5;
    stars = stars + 3;
    show(stars);
11. 11.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
12. 12.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud leaderboard (d) a cloud backup
13. 13.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.💾 What number does this code show?
    let stars = 7;
    stars = stars - 2;
    stars = stars + 1;
    show(stars);
15. 15.💾 What number does this code show?
    let notes = ["Maths", "Art", "Science"];
    notes.push("Music");
    notes.push("Hindi");
    show(notes.length);
16. 16.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
17. 17.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Rain", "Kites", "Sunrise"];
    show(songs[0]); (a) Sunrise (b) Kites (c) Stars (d) Rain
18. 18.Which of these fits saving on the phone? (a) a class leaderboard (b) the sound on/off setting (c) photos on two devices (d) a shared to-do list
19. 19.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Kites", "Monsoon", "Rain", "Ocean"];
    show(songs[1]); (a) Stars (b) Monsoon (c) Kites (d) Rain
20. 20.💾 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
21. 21.💾 What number does this code show?
    let points = 3;
    points = points - 3;
    points = points + 1;
    show(points);
22. 22.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Sports", "Maths"];
    show(notes[0]); (a) Science (b) Maths (c) Art (d) Sports
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Sports
25. 25.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
26. 26.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) photos on two devices (d) a draft you are typing
27. 27.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
28. 28.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) shrink the app (c) never need a password (d) skip the internet
29. 29.Which of these fits saving in the cloud? (a) notes to read offline (b) chat messages to friends (c) a draft you are typing (d) the sound on/off setting
30. 30.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 5;
    show(lives);
31. 31.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) the sound on/off setting
32. 32.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the phone is lost (c) the screen turns off (d) you send a message
33. 33.💾 What number does this code show?
    let songs = ["Sunrise", "Monsoon"];
    songs.push("Stars");
    songs.push("Rain");
    show(songs.length);
34. 34.💾 What number does this code show?
    let coins = 7;
    coins = coins - 4;
    coins = coins + 5;
    show(coins);
35. 35.💾 What is a variable? (a) a picture (b) a named box for a value (c) a type of screen (d) a phone setting
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Kabir", "Arjun"];
    show(friends[0]); (a) Kabir (b) Zoya (c) Arjun
37. 37.💾 What number does this code show?
    let stars = 5;
    stars = stars - 2;
    stars = stars + 2;
    show(stars);
38. 38.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Rain", "Sunrise", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Sunrise (d) Stars
39. 39.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Hindi"];
    show(notes[1]); (a) Science (b) Music (c) Hindi
40. 40.💾 What number does this code show?
    let songs = ["Ocean", "Monsoon", "Sunrise"];
    songs.push("Kites");
    show(songs.length);

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