App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 839 · 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 coins = 4;
   coins = coins - 4;
   coins = coins + 5;
   show(coins);
2. 2.💾 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
3. 3.💾 What number does this code show?
   let songs = ["Stars", "Ocean"];
   songs.push("Monsoon");
   songs.push("Sunrise");
   show(songs.length);
4. 4.💾 What is a variable? (a) a picture (b) a type of screen (c) a named box for a value (d) a phone setting
5. 5.True or false: your last game level fits saving in the cloud. (a) False (b) True
6. 6.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud backup (c) a cloud leaderboard (d) a shared chat
7. 7.💾 What number does this code show?
   let lives = 5;
   lives = lives - 2;
   lives = lives + 2;
   show(lives);
8. 8.Which of these fits saving in the cloud? (a) a shared to-do list (b) a draft you are typing (c) notes to read offline (d) your last game level
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Monsoon", "Ocean", "Kites"];
   show(songs[0]); (a) Monsoon (b) Stars (c) Ocean (d) Kites
10. 10.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Hindi", "Music"];
    show(notes[3]); (a) Hindi (b) Music (c) Maths (d) Science
11. 11.💾 What number does this code show?
    let points = 7;
    points = points - 1;
    points = points + 1;
    show(points);
12. 12.Which of these fits saving in the cloud? (a) a draft you are typing (b) chat messages to friends (c) your last game level (d) notes to read offline
13. 13.💾 What number does this code show?
    let songs = ["Monsoon", "Rain", "Stars"];
    songs.push("Sunrise");
    show(songs.length);
14. 14.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) notes to read offline (d) photos on two devices
15. 15.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) your last game level (d) a shared to-do list
16. 16.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) the phone is lost (d) you send a message
17. 17.Which of these fits saving in the cloud? (a) a class leaderboard (b) a draft you are typing (c) notes to read offline (d) your last game level
18. 18.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
19. 19.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) shrink the app (d) use it on any device
20. 20.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 2;
    show(coins);
21. 21.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
22. 22.True or false: your last game level fits saving on the phone. (a) True (b) False
23. 23.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Rain", "Monsoon", "Kites", "Sunrise"];
    show(songs[3]); (a) Kites (b) Monsoon (c) Rain (d) Ocean
24. 24.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Science (c) Hindi
25. 25.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 10 (c) 0 (d) 2
26. 26.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
27. 27.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
28. 28.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Maths", "Art", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Sports (c) Maths (d) Art
29. 29.💾 What number does this code show?
    let stars = 8;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
30. 30.💾 Which can hold many values in order? (a) a single number (b) a button (c) a switch (d) a list
31. 31.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Meera", "Aman", "Riya", "Arjun"];
    show(friends[0]); (a) Zoya (b) Aman (c) Riya (d) Meera
32. 32.💾 What number does this code show?
    let notes = ["Maths", "Art", "Science", "Hindi"];
    notes.push("Sports");
    show(notes.length);
33. 33.💾 What number does this code show?
    let friends = ["Arjun", "Aman", "Riya", "Zoya"];
    friends.push("Kabir");
    show(friends.length);
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Zoya", "Kabir", "Aman"];
    show(friends[0]); (a) Aman (b) Kabir (c) Zoya (d) Riya
35. 35.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
36. 36.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Hindi", "Art", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Hindi (c) Maths (d) Art
37. 37.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
38. 38.💾 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
39. 39.True or false: notes to read offline fits saving on the phone. (a) True (b) False
40. 40.💾 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

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