App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 299 · 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.💾 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
2. 2.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) data saved on the phone (d) a cloud leaderboard
3. 3.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) chat messages to friends (d) the sound on/off setting
4. 4.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
5. 5.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
6. 6.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 2 (d) 0
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.💾 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
9. 9.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) photos on two devices (d) a draft you are typing
10. 10.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Hindi", "Maths", "Music"];
    show(notes[1]); (a) Science (b) Maths (c) Hindi (d) Music
11. 11.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Ocean"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
12. 12.💾 What number does this code show?
    let songs = ["Monsoon", "Kites", "Sunrise", "Rain"];
    songs.push("Ocean");
    show(songs.length);
13. 13.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
14. 14.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a class leaderboard (d) the sound on/off setting
15. 15.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) photos on two devices (d) notes to read offline
16. 16.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) use it on any device (d) skip the internet
17. 17.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Riya", "Kabir", "Zoya"];
    show(friends[1]); (a) Aman (b) Zoya (c) Kabir (d) Riya
18. 18.💾 What number does this code show?
    let lives = 3;
    lives = lives - 3;
    lives = lives + 4;
    show(lives);
19. 19.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Art (c) Music
20. 20.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
21. 21.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
22. 22.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) in the cloud (b) on the phone
23. 23.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 5;
    show(score);
24. 24.Which of these fits saving on the phone? (a) the sound on/off setting (b) photos on two devices (c) chat messages to friends (d) a shared to-do list
25. 25.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Sunrise", "Ocean"];
    songs.push("Kites");
    show(songs.length);
26. 26.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
27. 27.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Sports", "Maths", "Music", "Art"];
    show(notes[2]); (a) Sports (b) Hindi (c) Music (d) Maths
28. 28.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) your last game level (d) a shared to-do list
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Music"];
    show(notes[0]); (a) Science (b) Maths (c) Music
30. 30.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Arjun", "Riya", "Kabir", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Arjun (d) Riya
31. 31.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Art", "Maths", "Science"];
    show(notes[0]); (a) Art (b) Hindi (c) Science (d) Maths
32. 32.True or false: your last game level fits saving on the phone. (a) True (b) False
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Hindi", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Hindi (c) Sports
34. 34.💾 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
35. 35.💾 What number does this code show?
    let friends = ["Kabir", "Aman"];
    friends.push("Arjun");
    friends.push("Zoya");
    show(friends.length);
36. 36.💾 What number does this code show?
    let notes = ["Science", "Art", "Music"];
    notes.push("Hindi");
    notes.push("Maths");
    show(notes.length);
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Music (c) Sports (d) Maths
38. 38.💾 What number does this code show?
    let score = 6;
    score = score - 6;
    score = score + 4;
    show(score);
39. 39.💾 What number does this code show?
    let lives = 5;
    lives = lives - 5;
    lives = lives + 5;
    show(lives);
40. 40.Which of these fits saving on the phone? (a) a shared to-do list (b) photos on two devices (c) a class leaderboard (d) your last game level

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