App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 937 · 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.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) the sound on/off setting (d) a shared to-do list
2. 2.💾 What number does this code show?
   let songs = ["Stars", "Kites"];
   songs.push("Ocean");
   show(songs.length);
3. 3.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
4. 4.💾 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
5. 5.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
6. 6.💾 pop() takes off the last item. What does this code show?
   let songs = ["Stars", "Ocean", "Monsoon", "Rain"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Rain (b) Stars (c) Ocean (d) Monsoon
7. 7.💾 What number does this code show?
   let notes = ["Sports", "Science", "Hindi"];
   notes.push("Music");
   show(notes.length);
8. 8.💾 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
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Monsoon", "Stars", "Sunrise", "Rain"];
   show(songs[0]); (a) Kites (b) Monsoon (c) Sunrise (d) Stars
10. 10.💾 What number does this code show?
    let friends = ["Kabir", "Meera"];
    friends.push("Riya");
    friends.push("Aman");
    show(friends.length);
11. 11.💾 Where should the app save a class leaderboard: 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) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
13. 13.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
14. 14.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
15. 15.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
16. 16.Which of these fits saving in the cloud? (a) a shared to-do list (b) notes to read offline (c) a draft you are typing (d) the sound on/off setting
17. 17.💾 What number does this code show?
    let points = 6;
    points = points - 1;
    points = points + 4;
    show(points);
18. 18.💾 What number does this code show?
    let songs = ["Ocean", "Rain", "Sunrise", "Kites"];
    songs.push("Monsoon");
    songs.push("Stars");
    show(songs.length);
19. 19.💾 What number does this code show?
    let score = 8;
    score = score - 1;
    score = score + 2;
    show(score);
20. 20.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) use it on any device (c) never need a password (d) shrink the app
21. 21.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Sunrise", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Ocean (c) Stars (d) Rain
22. 22.💾 What number does this code show?
    let stars = 7;
    stars = stars - 1;
    stars = stars + 5;
    show(stars);
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Music", "Hindi", "Maths", "Sports"];
    show(notes[3]); (a) Music (b) Art (c) Hindi (d) Maths
24. 24.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) notes to read offline (d) photos on two devices
25. 25.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Sunrise", "Ocean", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Rain (c) Ocean (d) Monsoon
26. 26.💾 What number does this code show?
    let notes = ["Sports", "Music", "Maths", "Art"];
    notes.push("Science");
    show(notes.length);
27. 27.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 10 (c) 0 (d) 2
28. 28.💾 What number does this code show?
    let points = 4;
    points = points - 1;
    points = points + 2;
    show(points);
29. 29.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
30. 30.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
31. 31.True or false: your last game level fits saving on the phone. (a) True (b) False
32. 32.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) a draft you are typing (d) photos on two devices
33. 33.💾 What number does this code show?
    let notes = ["Hindi", "Sports", "Music"];
    notes.push("Art");
    notes.push("Maths");
    show(notes.length);
34. 34.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Art", "Hindi"];
    show(notes[1]); (a) Sports (b) Art (c) Hindi (d) Music
35. 35.💾 What is a variable? (a) a type of screen (b) a named box for a value (c) a phone setting (d) a picture
36. 36.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
37. 37.💾 What number does this code show?
    let coins = 8;
    coins = coins - 1;
    coins = coins + 1;
    show(coins);
38. 38.💾 What number does this code show?
    let notes = ["Sports", "Maths", "Hindi"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
39. 39.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
40. 40.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Maths", "Science", "Sports"];
    show(notes[3]); (a) Science (b) Maths (c) Art (d) Sports

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