App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 640 · 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 a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
3. 3.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
4. 4.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
5. 5.💾 What does this code show? (Positions start at 0.)
   let notes = ["Music", "Sports", "Hindi", "Art"];
   show(notes[0]); (a) Hindi (b) Sports (c) Music (d) Art
6. 6.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) never need a password (d) use it on any device
7. 7.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Aman", "Zoya", "Meera", "Arjun"];
   show(friends[3]); (a) Riya (b) Meera (c) Aman (d) Zoya
8. 8.True or false: your last game level fits saving in the cloud. (a) True (b) False
9. 9.💾 What is a variable? (a) a picture (b) a phone setting (c) a type of screen (d) a named box for a value
10. 10.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Music", "Hindi", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Music (d) Art
12. 12.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
13. 13.True or false: notes to read offline fits saving on the phone. (a) True (b) False
14. 14.💾 What number does this code show?
    let friends = ["Arjun", "Zoya"];
    friends.push("Kabir");
    friends.push("Aman");
    show(friends.length);
15. 15.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Riya (c) Kabir
16. 16.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
17. 17.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Monsoon", "Rain", "Ocean"];
    show(songs[2]); (a) Monsoon (b) Rain (c) Sunrise (d) Ocean
18. 18.💾 What number does this code show?
    let score = 8;
    score = score - 7;
    score = score + 2;
    show(score);
19. 19.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Sunrise", "Ocean", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Ocean (c) Sunrise (d) Rain
20. 20.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
21. 21.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Riya", "Aman", "Meera", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Riya (c) Meera (d) Aman
22. 22.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Maths", "Hindi"];
    show(notes[0]); (a) Hindi (b) Maths (c) Sports (d) Music
23. 23.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
24. 24.💾 What number does this code show?
    let friends = ["Kabir", "Riya", "Meera", "Aman"];
    friends.push("Zoya");
    show(friends.length);
25. 25.💾 What number does this code show?
    let notes = ["Art", "Music"];
    notes.push("Hindi");
    show(notes.length);
26. 26.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 1;
    show(stars);
27. 27.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
28. 28.💾 What number does this code show?
    let lives = 7;
    lives = lives - 5;
    lives = lives + 5;
    show(lives);
29. 29.Which of these fits saving in the cloud? (a) notes to read offline (b) chat messages to friends (c) the sound on/off setting (d) a draft you are typing
30. 30.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) the sound on/off setting
31. 31.💾 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
32. 32.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Kites (c) Monsoon
33. 33.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) data saved on the phone (d) a shared chat
34. 34.💾 What number does this code show?
    let stars = 3;
    stars = stars - 3;
    stars = stars + 4;
    show(stars);
35. 35.💾 What number does this code show?
    let lives = 4;
    lives = lives - 4;
    lives = lives + 2;
    show(lives);
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Rain", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Rain
37. 37.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
38. 38.💾 Which can hold many values in order? (a) a list (b) a single number (c) a switch (d) a button
39. 39.💾 What number does this code show?
    let songs = ["Monsoon", "Ocean", "Kites"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
40. 40.💾 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

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