App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 739 · 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 works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud backup (d) a cloud leaderboard
2. 2.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
3. 3.True or false: your last game level fits saving in the cloud. (a) False (b) True
4. 4.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
5. 5.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
6. 6.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) photos on two devices (d) notes to read offline
7. 7.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) use it on any device (d) skip the internet
8. 8.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
9. 9.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) notes to read offline (d) chat messages to friends
10. 10.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
11. 11.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Art", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Art (c) Science
12. 12.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Sunrise", "Monsoon", "Stars"];
    show(songs[1]); (a) Monsoon (b) Sunrise (c) Kites (d) Stars
13. 13.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) your last game level (d) chat messages to friends
14. 14.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) a shared to-do list (d) the sound on/off setting
15. 15.💾 What number does this code show?
    let stars = 7;
    stars = stars - 6;
    stars = stars + 3;
    show(stars);
16. 16.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
17. 17.💾 What number does this code show?
    let points = 5;
    points = points - 1;
    points = points + 5;
    show(points);
18. 18.💾 What number does this code show?
    let notes = ["Sports", "Hindi", "Music", "Science"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
19. 19.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Monsoon", "Sunrise"];
    show(songs[0]); (a) Ocean (b) Sunrise (c) Monsoon
20. 20.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon", "Ocean"];
    songs.push("Stars");
    show(songs.length);
21. 21.💾 What number does this code show?
    let score = 8;
    score = score - 1;
    score = score + 1;
    show(score);
22. 22.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
23. 23.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) a class leaderboard (d) your last game level
24. 24.💾 What number does this code show?
    let score = 4;
    score = score - 1;
    score = score + 4;
    show(score);
25. 25.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 1 (c) 2 (d) 10
26. 26.💾 What number does this code show?
    let points = 3;
    points = points - 3;
    points = points + 2;
    show(points);
27. 27.💾 What is a variable? (a) a named box for a value (b) a phone setting (c) a picture (d) a type of screen
28. 28.💾 What number does this code show?
    let coins = 7;
    coins = coins - 5;
    coins = coins + 3;
    show(coins);
29. 29.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
30. 30.True or false: notes to read offline fits saving on the phone. (a) True (b) False
31. 31.💾 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
32. 32.💾 What number does this code show?
    let stars = 6;
    stars = stars - 2;
    stars = stars + 3;
    show(stars);
33. 33.💾 What number does this code show?
    let friends = ["Riya", "Arjun"];
    friends.push("Meera");
    show(friends.length);
34. 34.True or false: your last game level fits saving on the phone. (a) True (b) False
35. 35.💾 What number does this code show?
    let friends = ["Riya", "Meera", "Zoya"];
    friends.push("Kabir");
    show(friends.length);
36. 36.💾 What number does this code show?
    let points = 9;
    points = points - 3;
    points = points + 3;
    show(points);
37. 37.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
39. 39.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Zoya"];
    show(friends[2]); (a) Zoya (b) Kabir (c) Aman

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