App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 881 · 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.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
2. 2.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a draft you are typing (d) photos on two devices
3. 3.💾 What number does this code show?
   let notes = ["Maths", "Hindi", "Sports", "Science"];
   notes.push("Art");
   notes.push("Music");
   show(notes.length);
4. 4.💾 What number does this code show?
   let friends = ["Aman", "Riya", "Arjun", "Meera"];
   friends.push("Kabir");
   friends.push("Zoya");
   show(friends.length);
5. 5.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) you send a message (c) the phone is lost (d) the app is closed
6. 6.💾 pop() takes off the last item. What does this code show?
   let friends = ["Meera", "Zoya", "Arjun", "Kabir"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Meera (b) Zoya (c) Kabir (d) Arjun
7. 7.💾 Which works with no internet at all? (a) a cloud backup (b) data saved on the phone (c) a shared chat (d) a cloud leaderboard
8. 8.💾 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
9. 9.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
10. 10.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
11. 11.💾 What number does this code show?
    let friends = ["Meera", "Aman", "Kabir"];
    friends.push("Arjun");
    show(friends.length);
12. 12.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Aman", "Arjun"];
    show(friends[1]); (a) Arjun (b) Kabir (c) Aman
13. 13.True or false: photos on two devices fits saving on the phone. (a) True (b) False
14. 14.💾 What number does this code show?
    let notes = ["Hindi", "Science"];
    notes.push("Sports");
    notes.push("Maths");
    show(notes.length);
15. 15.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Meera", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Aman (c) Meera
16. 16.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Riya", "Kabir"];
    show(friends[2]); (a) Riya (b) Kabir (c) Arjun
17. 17.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
18. 18.Which of these fits saving in the cloud? (a) a class leaderboard (b) a draft you are typing (c) your last game level (d) notes to read offline
19. 19.💾 What number does this code show?
    let score = 5;
    score = score - 4;
    score = score + 4;
    show(score);
20. 20.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
21. 21.💾 What number does this code show?
    let songs = ["Stars", "Ocean"];
    songs.push("Kites");
    show(songs.length);
22. 22.💾 What number does this code show?
    let songs = ["Rain", "Kites"];
    songs.push("Monsoon");
    show(songs.length);
23. 23.💾 What is a variable? (a) a picture (b) a type of screen (c) a phone setting (d) a named box for a value
24. 24.True or false: your last game level fits saving in the cloud. (a) False (b) True
25. 25.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Science", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Hindi (c) Art (d) Maths
26. 26.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Sports", "Hindi", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Hindi (c) Maths (d) Sports
27. 27.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
28. 28.Which of these fits saving in the cloud? (a) a shared to-do list (b) the sound on/off setting (c) notes to read offline (d) your last game level
29. 29.💾 What number does this code show?
    let friends = ["Zoya", "Arjun"];
    friends.push("Kabir");
    show(friends.length);
30. 30.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
31. 31.💾 What number does this code show?
    let notes = ["Sports", "Music", "Science", "Hindi"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
32. 32.True or false: your last game level fits saving on the phone. (a) True (b) False
33. 33.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
34. 34.💾 Which can hold many values in order? (a) a list (b) a switch (c) a button (d) a single number
35. 35.💾 What number does this code show?
    let notes = ["Science", "Hindi"];
    notes.push("Art");
    notes.push("Sports");
    show(notes.length);
36. 36.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
37. 37.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Kabir", "Meera"];
    show(friends[0]); (a) Aman (b) Meera (c) Riya (d) Kabir
38. 38.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a class leaderboard (d) chat messages to friends
39. 39.💾 What number does this code show?
    let lives = 7;
    lives = lives - 5;
    lives = lives + 2;
    show(lives);
40. 40.💾 What number does this code show?
    let friends = ["Kabir", "Arjun", "Riya", "Meera"];
    friends.push("Zoya");
    show(friends.length);

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