App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 548 · 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.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
2. 2.💾 pop() takes off the last item. What does this code show?
   let notes = ["Sports", "Maths", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Maths (c) Sports
3. 3.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) your last game level (d) chat messages to friends
4. 4.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
5. 5.💾 pop() takes off the last item. What does this code show?
   let songs = ["Ocean", "Kites", "Monsoon"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Monsoon (b) Kites (c) Ocean
6. 6.💾 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
7. 7.💾 pop() takes off the last item. What does this code show?
   let songs = ["Sunrise", "Ocean", "Rain", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Sunrise (d) Stars
8. 8.True or false: photos on two devices fits saving on the phone. (a) True (b) False
9. 9.💾 Saving data in the cloud lets you ___. (a) never need a password (b) use it on any device (c) shrink the app (d) skip the internet
10. 10.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 5;
    show(score);
11. 11.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Ocean", "Monsoon", "Kites", "Stars"];
    show(songs[3]); (a) Rain (b) Kites (c) Ocean (d) Monsoon
12. 12.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
13. 13.💾 What number does this code show?
    let friends = ["Riya", "Aman", "Arjun"];
    friends.push("Meera");
    show(friends.length);
14. 14.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) data saved on the phone (d) a cloud backup
15. 15.💾 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
16. 16.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
17. 17.💾 Which can hold many values in order? (a) a single number (b) a list (c) a switch (d) a button
18. 18.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Stars", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Rain (c) Sunrise (d) Monsoon
19. 19.💾 What number does this code show?
    let stars = 8;
    stars = stars - 5;
    stars = stars + 2;
    show(stars);
20. 20.💾 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
21. 21.💾 What number does this code show?
    let stars = 4;
    stars = stars - 1;
    stars = stars + 2;
    show(stars);
22. 22.💾 What number does this code show?
    let coins = 8;
    coins = coins - 1;
    coins = coins + 5;
    show(coins);
23. 23.💾 What number does this code show?
    let notes = ["Art", "Maths"];
    notes.push("Hindi");
    notes.push("Sports");
    show(notes.length);
24. 24.💾 What number does this code show?
    let notes = ["Maths", "Science", "Hindi"];
    notes.push("Art");
    show(notes.length);
25. 25.True or false: notes to read offline fits saving on the phone. (a) False (b) True
26. 26.True or false: your last game level fits saving on the phone. (a) False (b) True
27. 27.Which of these fits saving on the phone? (a) chat messages to friends (b) your last game level (c) a shared to-do list (d) photos on two devices
28. 28.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Kites", "Ocean", "Monsoon"];
    show(songs[1]); (a) Kites (b) Ocean (c) Rain (d) Sunrise
29. 29.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
30. 30.💾 What number does this code show?
    let points = 4;
    points = points - 1;
    points = points + 1;
    show(points);
31. 31.💾 What number does this code show?
    let notes = ["Art", "Music", "Maths", "Science"];
    notes.push("Sports");
    show(notes.length);
32. 32.💾 What number does this code show?
    let songs = ["Stars", "Rain", "Kites"];
    songs.push("Ocean");
    songs.push("Sunrise");
    show(songs.length);
33. 33.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a picture (d) a named box for a value
34. 34.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
36. 36.💾 What number does this code show?
    let notes = ["Art", "Hindi", "Music"];
    notes.push("Maths");
    notes.push("Science");
    show(notes.length);
37. 37.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.💾 What number does this code show?
    let coins = 6;
    coins = coins - 1;
    coins = coins + 5;
    show(coins);
39. 39.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) notes to read offline (d) photos on two devices
40. 40.True or false: photos on two devices fits saving in the cloud. (a) True (b) False

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