App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 872 · 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 class leaderboard fits saving on the phone. (a) True (b) False
2. 2.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
3. 3.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the phone is lost (c) the app is closed (d) you send a message
4. 4.💾 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
5. 5.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
6. 6.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
7. 7.💾 What number does this code show?
   let notes = ["Science", "Sports", "Maths", "Art"];
   notes.push("Hindi");
   notes.push("Music");
   show(notes.length);
8. 8.💾 pop() takes off the last item. What does this code show?
   let notes = ["Maths", "Sports", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Hindi
9. 9.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
10. 10.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
11. 11.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
12. 12.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) skip the internet (d) use it on any device
13. 13.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Sunrise", "Rain", "Monsoon", "Kites"];
    show(songs[1]); (a) Sunrise (b) Monsoon (c) Rain (d) Stars
15. 15.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Hindi", "Music", "Science", "Sports"];
    show(notes[3]); (a) Maths (b) Music (c) Hindi (d) Science
16. 16.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Meera", "Zoya", "Aman"];
    show(friends[3]); (a) Kabir (b) Aman (c) Zoya (d) Meera
17. 17.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) the sound on/off setting (d) a class leaderboard
18. 18.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Hindi", "Art"];
    notes.push("Science");
    show(notes.length);
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Maths", "Sports", "Music", "Art"];
    show(notes[4]); (a) Art (b) Maths (c) Sports (d) Hindi
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Science", "Art", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Science (d) Art
21. 21.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) a shared to-do list (d) notes to read offline
22. 22.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
23. 23.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Aman", "Zoya", "Kabir"];
    show(friends[2]); (a) Aman (b) Zoya (c) Kabir (d) Riya
24. 24.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) a draft you are typing (d) chat messages to friends
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.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
27. 27.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
28. 28.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 1 (d) 10
29. 29.💾 What number does this code show?
    let friends = ["Riya", "Arjun", "Zoya", "Aman"];
    friends.push("Meera");
    friends.push("Kabir");
    show(friends.length);
30. 30.💾 What number does this code show?
    let notes = ["Science", "Hindi", "Maths"];
    notes.push("Sports");
    show(notes.length);
31. 31.💾 What number does this code show?
    let lives = 3;
    lives = lives - 2;
    lives = lives + 3;
    show(lives);
32. 32.💾 What number does this code show?
    let score = 4;
    score = score - 1;
    score = score + 1;
    show(score);
33. 33.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
34. 34.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Zoya (d) Riya
35. 35.💾 What number does this code show?
    let notes = ["Science", "Maths", "Hindi", "Art"];
    notes.push("Music");
    show(notes.length);
36. 36.💾 What number does this code show?
    let score = 7;
    score = score - 1;
    score = score + 2;
    show(score);
37. 37.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
38. 38.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Hindi (c) Science
39. 39.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Sports", "Music"];
    show(notes[3]); (a) Science (b) Maths (c) Sports (d) Music
40. 40.💾 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

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