App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 690 · 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) a cloud leaderboard (c) a cloud backup (d) data saved on the phone
2. 2.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.💾 What does this code show? (Positions start at 0.)
   let notes = ["Maths", "Sports", "Art"];
   show(notes[0]); (a) Sports (b) Maths (c) Art
4. 4.💾 pop() takes off the last item. What does this code show?
   let songs = ["Stars", "Ocean", "Monsoon", "Sunrise"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Monsoon (b) Stars (c) Sunrise (d) Ocean
5. 5.💾 What number does this code show?
   let stars = 6;
   stars = stars - 4;
   stars = stars + 3;
   show(stars);
6. 6.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a draft you are typing (d) chat messages to friends
7. 7.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
8. 8.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
9. 9.Which of these fits saving in the cloud? (a) notes to read offline (b) chat messages to friends (c) your last game level (d) a draft you are typing
10. 10.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the phone is lost (d) the app is closed
11. 11.True or false: notes to read offline fits saving on the phone. (a) False (b) True
12. 12.💾 What number does this code show?
    let coins = 7;
    coins = coins - 4;
    coins = coins + 1;
    show(coins);
13. 13.True or false: photos on two devices fits saving on the phone. (a) True (b) False
14. 14.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
15. 15.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
16. 16.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Hindi", "Music"];
    show(notes[2]); (a) Hindi (b) Science (c) Music
17. 17.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 0 (c) 1 (d) 10
18. 18.💾 What number does this code show?
    let friends = ["Kabir", "Arjun", "Meera", "Aman"];
    friends.push("Zoya");
    friends.push("Riya");
    show(friends.length);
19. 19.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) shrink the app (d) use it on any device
20. 20.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) photos on two devices (d) the sound on/off setting
21. 21.💾 What is a variable? (a) a type of screen (b) a picture (c) a phone setting (d) a named box for a value
22. 22.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) your last game level (d) photos on two devices
23. 23.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Monsoon", "Ocean"];
    show(songs[0]); (a) Monsoon (b) Ocean (c) Rain
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Sports", "Music"];
    show(notes[0]); (a) Music (b) Sports (c) Hindi
25. 25.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
26. 26.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) notes to read offline (d) a class leaderboard
27. 27.💾 What number does this code show?
    let lives = 3;
    lives = lives - 2;
    lives = lives + 2;
    show(lives);
28. 28.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Sports", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Art (c) Sports
30. 30.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Arjun", "Riya", "Kabir", "Meera"];
    show(friends[4]); (a) Meera (b) Riya (c) Zoya (d) Arjun
31. 31.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Music", "Sports", "Science", "Art"];
    show(notes[3]); (a) Sports (b) Music (c) Maths (d) Science
32. 32.💾 What number does this code show?
    let stars = 6;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
33. 33.💾 What number does this code show?
    let notes = ["Maths", "Science", "Music", "Hindi"];
    notes.push("Art");
    show(notes.length);
34. 34.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 2;
    show(lives);
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Arjun", "Zoya"];
    show(friends[0]); (a) Zoya (b) Kabir (c) Arjun
36. 36.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Stars", "Kites", "Ocean", "Rain"];
    show(songs[2]); (a) Ocean (b) Stars (c) Monsoon (d) Kites
37. 37.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Rain", "Kites", "Monsoon"];
    show(songs[2]); (a) Monsoon (b) Stars (c) Rain (d) Kites
38. 38.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
39. 39.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) notes to read offline (d) a class leaderboard
40. 40.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Hindi", "Art", "Science", "Sports"];
    show(notes[4]); (a) Art (b) Sports (c) Maths (d) Hindi

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