App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 817 · 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) data saved on the phone (b) a shared chat (c) a cloud leaderboard (d) a cloud backup
2. 2.💾 What does this code show? (Positions start at 0.)
   let notes = ["Sports", "Science", "Art", "Maths", "Hindi"];
   show(notes[4]); (a) Sports (b) Hindi (c) Science (d) Art
3. 3.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
4. 4.💾 What does this code show? (Positions start at 0.)
   let friends = ["Arjun", "Zoya", "Aman", "Meera", "Riya"];
   show(friends[2]); (a) Meera (b) Arjun (c) Aman (d) Zoya
5. 5.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) a shared to-do list (d) your last game level
6. 6.💾 What number does this code show?
   let friends = ["Riya", "Kabir", "Aman", "Zoya"];
   friends.push("Meera");
   show(friends.length);
7. 7.💾 pop() takes off the last item. What does this code show?
   let songs = ["Kites", "Monsoon", "Sunrise", "Ocean", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Monsoon (b) Kites (c) Sunrise (d) Ocean
8. 8.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) photos on two devices (d) notes to read offline
9. 9.💾 What number does this code show?
   let notes = ["Science", "Maths", "Sports"];
   notes.push("Music");
   show(notes.length);
10. 10.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 10 (c) 2 (d) 0
11. 11.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) the phone is lost (d) you send a message
12. 12.💾 What number does this code show?
    let lives = 4;
    lives = lives - 4;
    lives = lives + 2;
    show(lives);
13. 13.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Sports"];
    show(notes[2]); (a) Art (b) Maths (c) Sports
14. 14.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
15. 15.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Kabir", "Arjun", "Meera"];
    show(friends[0]); (a) Arjun (b) Aman (c) Kabir (d) Riya
16. 16.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) a class leaderboard (d) notes to read offline
17. 17.💾 What number does this code show?
    let points = 3;
    points = points - 1;
    points = points + 3;
    show(points);
18. 18.💾 What number does this code show?
    let songs = ["Monsoon", "Rain"];
    songs.push("Kites");
    show(songs.length);
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Science", "Hindi"];
    show(notes[1]); (a) Sports (b) Science (c) Hindi
20. 20.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
21. 21.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) use it on any device (c) shrink the app (d) never need a password
22. 22.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
23. 23.💾 What number does this code show?
    let notes = ["Music", "Science"];
    notes.push("Art");
    show(notes.length);
24. 24.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Kabir", "Zoya", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Zoya (d) Meera
25. 25.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
26. 26.💾 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
27. 27.💾 What number does this code show?
    let friends = ["Arjun", "Meera", "Riya"];
    friends.push("Kabir");
    friends.push("Aman");
    show(friends.length);
28. 28.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Sunrise", "Stars", "Rain"];
    show(songs[1]); (a) Rain (b) Stars (c) Monsoon (d) Sunrise
29. 29.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
30. 30.💾 What number does this code show?
    let lives = 7;
    lives = lives - 4;
    lives = lives + 4;
    show(lives);
31. 31.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Aman", "Kabir"];
    show(friends[2]); (a) Kabir (b) Meera (c) Aman
32. 32.💾 What is a variable? (a) a picture (b) a type of screen (c) a phone setting (d) a named box for a value
33. 33.💾 What number does this code show?
    let score = 8;
    score = score - 5;
    score = score + 4;
    show(score);
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Arjun", "Aman", "Riya"];
    show(friends[2]); (a) Riya (b) Meera (c) Arjun (d) Aman
35. 35.💾 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
36. 36.💾 What number does this code show?
    let songs = ["Rain", "Kites"];
    songs.push("Stars");
    songs.push("Monsoon");
    show(songs.length);
37. 37.True or false: photos on two devices fits saving on the phone. (a) True (b) False
38. 38.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
39. 39.Which of these fits saving in the cloud? (a) your last game level (b) photos on two devices (c) a draft you are typing (d) the sound on/off setting
40. 40.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Kites", "Rain", "Stars", "Sunrise"];
    show(songs[4]); (a) Kites (b) Rain (c) Sunrise (d) Ocean

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