App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 27 · 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.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 10 (d) 1
2. 2.💾 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
3. 3.💾 What number does this code show?
   let score = 6;
   score = score - 1;
   score = score + 1;
   show(score);
4. 4.💾 pop() takes off the last item. What does this code show?
   let notes = ["Sports", "Hindi", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Hindi (c) Art
5. 5.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Monsoon", "Rain"];
   show(songs[0]); (a) Rain (b) Monsoon (c) Stars
6. 6.💾 What number does this code show?
   let friends = ["Kabir", "Aman"];
   friends.push("Arjun");
   friends.push("Meera");
   show(friends.length);
7. 7.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Arjun", "Kabir", "Meera"];
   show(friends[0]); (a) Meera (b) Kabir (c) Arjun (d) Riya
8. 8.Which of these fits saving in the cloud? (a) the sound on/off setting (b) photos on two devices (c) a draft you are typing (d) notes to read offline
9. 9.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) the sound on/off setting (d) a class leaderboard
10. 10.True or false: photos on two devices fits saving on the phone. (a) False (b) True
11. 11.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) notes to read offline (d) a shared to-do list
12. 12.Which of these fits saving on the phone? (a) a draft you are typing (b) a class leaderboard (c) photos on two devices (d) chat messages to friends
13. 13.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a picture (d) a named box for a value
15. 15.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Science", "Music", "Art", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Science (c) Sports (d) Music
16. 16.💾 Which works with no internet at all? (a) a shared chat (b) a cloud backup (c) a cloud leaderboard (d) data saved on the phone
17. 17.💾 What number does this code show?
    let songs = ["Stars", "Monsoon"];
    songs.push("Ocean");
    songs.push("Rain");
    show(songs.length);
18. 18.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Stars", "Rain", "Sunrise"];
    show(songs[2]); (a) Stars (b) Rain (c) Ocean (d) Sunrise
19. 19.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Stars", "Rain"];
    show(songs[0]); (a) Stars (b) Kites (c) Rain
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Maths", "Science", "Music", "Sports"];
    show(notes[1]); (a) Art (b) Maths (c) Music (d) Science
21. 21.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Ocean", "Monsoon"];
    show(songs[1]); (a) Sunrise (b) Monsoon (c) Ocean
22. 22.💾 What number does this code show?
    let lives = 5;
    lives = lives - 2;
    lives = lives + 5;
    show(lives);
23. 23.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Ocean", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Rain (c) Ocean
24. 24.💾 What number does this code show?
    let notes = ["Hindi", "Art"];
    notes.push("Maths");
    show(notes.length);
25. 25.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) your last game level (d) chat messages to friends
26. 26.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Maths", "Science", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Hindi (c) Maths (d) Art
27. 27.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
28. 28.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
29. 29.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the app is closed (c) the phone is lost (d) you send a message
30. 30.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
31. 31.True or false: notes to read offline fits saving on the phone. (a) False (b) True
32. 32.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Hindi", "Art"];
    show(notes[0]); (a) Art (b) Science (c) Hindi
34. 34.💾 What number does this code show?
    let songs = ["Monsoon", "Stars", "Sunrise"];
    songs.push("Rain");
    show(songs.length);
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Riya", "Zoya"];
    show(friends[1]); (a) Riya (b) Aman (c) Zoya
36. 36.💾 What number does this code show?
    let songs = ["Kites", "Rain", "Stars"];
    songs.push("Ocean");
    show(songs.length);
37. 37.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
38. 38.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Ocean", "Rain"];
    show(songs[1]); (a) Rain (b) Ocean (c) Monsoon
39. 39.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
40. 40.💾 What number does this code show?
    let friends = ["Riya", "Aman"];
    friends.push("Arjun");
    show(friends.length);

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