App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 219 · 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 can hold many values in order? (a) a button (b) a list (c) a switch (d) a single number
2. 2.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 10 (d) 0
3. 3.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
4. 4.Which of these fits saving in the cloud? (a) a class leaderboard (b) your last game level (c) the sound on/off setting (d) notes to read offline
5. 5.💾 What number does this code show?
   let lives = 4;
   lives = lives - 2;
   lives = lives + 5;
   show(lives);
6. 6.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) chat messages to friends (d) notes to read offline
7. 7.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
8. 8.💾 What number does this code show?
   let songs = ["Ocean", "Stars", "Rain"];
   songs.push("Sunrise");
   show(songs.length);
9. 9.💾 What number does this code show?
   let friends = ["Meera", "Arjun"];
   friends.push("Riya");
   show(friends.length);
10. 10.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean"];
    songs.push("Stars");
    show(songs.length);
11. 11.💾 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
12. 12.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) notes to read offline (d) a shared to-do list
13. 13.Which of these fits saving in the cloud? (a) your last game level (b) the sound on/off setting (c) a draft you are typing (d) a shared to-do list
14. 14.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 5;
    show(stars);
15. 15.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) a cloud backup (d) data saved on the phone
16. 16.💾 What is a variable? (a) a type of screen (b) a picture (c) a phone setting (d) a named box for a value
17. 17.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
18. 18.💾 What number does this code show?
    let notes = ["Hindi", "Maths"];
    notes.push("Sports");
    show(notes.length);
19. 19.True or false: your last game level fits saving on the phone. (a) True (b) False
20. 20.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
21. 21.True or false: your last game level fits saving in the cloud. (a) False (b) True
22. 22.💾 What number does this code show?
    let score = 9;
    score = score - 8;
    score = score + 4;
    show(score);
23. 23.💾 What number does this code show?
    let songs = ["Kites", "Rain", "Ocean"];
    songs.push("Sunrise");
    show(songs.length);
24. 24.💾 What number does this code show?
    let friends = ["Aman", "Riya", "Arjun"];
    friends.push("Kabir");
    friends.push("Zoya");
    show(friends.length);
25. 25.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
26. 26.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.💾 What number does this code show?
    let coins = 6;
    coins = coins - 6;
    coins = coins + 5;
    show(coins);
28. 28.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Maths", "Music", "Art", "Hindi"];
    show(notes[0]); (a) Science (b) Music (c) Art (d) Maths
29. 29.True or false: notes to read offline fits saving on the phone. (a) True (b) False
30. 30.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) the sound on/off setting (d) photos on two devices
31. 31.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
32. 32.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) use it on any device (d) never need a password
33. 33.💾 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
34. 34.💾 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
35. 35.💾 What number does this code show?
    let notes = ["Maths", "Hindi"];
    notes.push("Art");
    notes.push("Music");
    show(notes.length);
36. 36.💾 What number does this code show?
    let points = 7;
    points = points - 2;
    points = points + 2;
    show(points);
37. 37.Which of these fits saving on the phone? (a) a class leaderboard (b) a draft you are typing (c) photos on two devices (d) chat messages to friends
38. 38.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Zoya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Kabir (c) Zoya
39. 39.💾 What number does this code show?
    let notes = ["Hindi", "Art"];
    notes.push("Science");
    notes.push("Maths");
    show(notes.length);
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Kabir", "Zoya"];
    show(friends[0]); (a) Riya (b) Kabir (c) Zoya (d) Arjun

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