App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 894 · 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 class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
2. 2.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
3. 3.💾 What number does this code show?
   let songs = ["Stars", "Ocean"];
   songs.push("Monsoon");
   show(songs.length);
4. 4.💾 What does this code show? (Positions start at 0.)
   let friends = ["Kabir", "Zoya", "Aman", "Meera"];
   show(friends[2]); (a) Meera (b) Kabir (c) Aman (d) Zoya
5. 5.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a draft you are typing (d) a shared to-do list
6. 6.💾 What number does this code show?
   let lives = 9;
   lives = lives - 7;
   lives = lives + 5;
   show(lives);
7. 7.💾 pop() takes off the last item. What does this code show?
   let notes = ["Hindi", "Music", "Art", "Science"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Hindi (b) Art (c) Science (d) Music
8. 8.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a button (d) a list
9. 9.💾 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
10. 10.💾 What number does this code show?
    let points = 5;
    points = points - 3;
    points = points + 1;
    show(points);
11. 11.💾 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
12. 12.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
13. 13.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Maths (c) Science
14. 14.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
15. 15.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Monsoon", "Stars", "Ocean", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Stars (c) Ocean (d) Rain
16. 16.💾 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
17. 17.💾 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
18. 18.💾 What number does this code show?
    let songs = ["Kites", "Sunrise", "Stars", "Rain"];
    songs.push("Ocean");
    songs.push("Monsoon");
    show(songs.length);
19. 19.💾 What number does this code show?
    let notes = ["Science", "Maths"];
    notes.push("Sports");
    show(notes.length);
20. 20.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
21. 21.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 1 (c) 10 (d) 2
22. 22.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a picture (d) a type of screen
23. 23.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) a draft you are typing (d) photos on two devices
24. 24.True or false: the sound on/off setting fits saving on the phone. (a) True (b) False
25. 25.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) you send a message (c) the app is closed (d) the phone is lost
26. 26.💾 What number does this code show?
    let points = 7;
    points = points - 4;
    points = points + 1;
    show(points);
27. 27.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Ocean", "Sunrise"];
    songs.push("Stars");
    songs.push("Kites");
    show(songs.length);
28. 28.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Rain", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Sunrise (c) Rain
29. 29.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) never need a password (d) skip the internet
30. 30.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
31. 31.💾 What number does this code show?
    let friends = ["Meera", "Arjun"];
    friends.push("Kabir");
    show(friends.length);
32. 32.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
33. 33.💾 What number does this code show?
    let notes = ["Sports", "Hindi"];
    notes.push("Science");
    show(notes.length);
34. 34.💾 What number does this code show?
    let score = 8;
    score = score - 3;
    score = score + 4;
    show(score);
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Kabir", "Aman"];
    show(friends[0]); (a) Aman (b) Meera (c) Kabir
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Rain (b) Kites (c) Sunrise
37. 37.💾 What number does this code show?
    let songs = ["Kites", "Stars", "Monsoon", "Ocean"];
    songs.push("Rain");
    songs.push("Sunrise");
    show(songs.length);
38. 38.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Stars", "Monsoon", "Ocean"];
    show(songs[2]); (a) Rain (b) Sunrise (c) Monsoon (d) Stars
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Stars"];
    show(songs[1]); (a) Rain (b) Sunrise (c) Stars
40. 40.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) a class leaderboard (d) your last game level

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