App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 439 · 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 in the cloud. (a) True (b) False
2. 2.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) data saved on the phone (d) a cloud backup
3. 3.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the app is closed (c) you send a message (d) the screen turns off
4. 4.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) a shared to-do list (d) a draft you are typing
6. 6.True or false: photos on two devices fits saving on the phone. (a) True (b) False
7. 7.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) chat messages to friends (d) the sound on/off setting
8. 8.💾 What number does this code show?
   let score = 5;
   score = score - 5;
   score = score + 1;
   show(score);
9. 9.💾 pop() takes off the last item. What does this code show?
   let notes = ["Music", "Maths", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Art (c) Music
10. 10.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
12. 12.True or false: your last game level fits saving on the phone. (a) False (b) True
13. 13.True or false: your last game level fits saving in the cloud. (a) True (b) False
14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Ocean", "Stars", "Rain"];
    show(songs[1]); (a) Stars (b) Rain (c) Ocean (d) Monsoon
15. 15.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Sunrise", "Kites", "Rain"];
    show(songs[1]); (a) Monsoon (b) Kites (c) Rain (d) Sunrise
16. 16.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
17. 17.💾 What number does this code show?
    let coins = 8;
    coins = coins - 1;
    coins = coins + 3;
    show(coins);
18. 18.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a shared to-do list (d) a class leaderboard
19. 19.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Riya", "Arjun", "Aman"];
    show(friends[1]); (a) Zoya (b) Arjun (c) Aman (d) Riya
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Music", "Maths"];
    show(notes[2]); (a) Maths (b) Music (c) Science
21. 21.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Zoya", "Meera"];
    show(friends[1]); (a) Kabir (b) Zoya (c) Meera (d) Aman
22. 22.💾 What number does this code show?
    let notes = ["Sports", "Hindi"];
    notes.push("Science");
    notes.push("Maths");
    show(notes.length);
23. 23.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Riya", "Meera"];
    show(friends[2]); (a) Kabir (b) Riya (c) Meera
24. 24.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
25. 25.💾 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
26. 26.💾 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
27. 27.💾 What number does this code show?
    let songs = ["Ocean", "Kites", "Stars", "Sunrise"];
    songs.push("Rain");
    songs.push("Monsoon");
    show(songs.length);
28. 28.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Arjun", "Meera"];
    show(friends[0]); (a) Meera (b) Arjun (c) Aman
29. 29.💾 What number does this code show?
    let score = 5;
    score = score - 3;
    score = score + 3;
    show(score);
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Sunrise", "Kites", "Stars", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Sunrise (c) Stars (d) Monsoon
31. 31.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) photos on two devices (d) a draft you are typing
32. 32.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
33. 33.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
34. 34.💾 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
35. 35.💾 What number does this code show?
    let songs = ["Ocean", "Sunrise", "Kites", "Stars"];
    songs.push("Rain");
    songs.push("Monsoon");
    show(songs.length);
36. 36.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Kites", "Monsoon"];
    show(songs[2]); (a) Monsoon (b) Kites (c) Sunrise
37. 37.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
38. 38.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a draft you are typing (d) chat messages to friends
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Hindi", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Science (c) Maths
40. 40.💾 What number does this code show?
    let points = 4;
    points = points - 2;
    points = points + 4;
    show(points);

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