App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 282 · 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: notes to read offline fits saving on the phone. (a) True (b) False
2. 2.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
3. 3.💾 What is a variable? (a) a phone setting (b) a picture (c) a named box for a value (d) a type of screen
4. 4.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
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.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 friends = ["Aman", "Meera"];
   friends.push("Riya");
   friends.push("Kabir");
   show(friends.length);
8. 8.💾 What number does this code show?
   let friends = ["Meera", "Riya", "Aman", "Zoya"];
   friends.push("Arjun");
   show(friends.length);
9. 9.💾 What does this code show? (Positions start at 0.)
   let songs = ["Stars", "Ocean", "Rain", "Monsoon", "Kites"];
   show(songs[1]); (a) Stars (b) Monsoon (c) Ocean (d) Rain
10. 10.💾 What number does this code show?
    let friends = ["Aman", "Riya", "Kabir"];
    friends.push("Arjun");
    show(friends.length);
11. 11.💾 Which can hold many values in order? (a) a switch (b) a list (c) a single number (d) a button
12. 12.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) a draft you are typing (d) a class leaderboard
13. 13.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Sports", "Maths", "Hindi"];
    show(notes[2]); (a) Maths (b) Science (c) Hindi (d) Sports
14. 14.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
15. 15.💾 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
16. 16.Which of these fits saving in the cloud? (a) notes to read offline (b) a shared to-do list (c) your last game level (d) a draft you are typing
17. 17.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a draft you are typing (d) a shared to-do list
18. 18.Which of these fits saving in the cloud? (a) chat messages to friends (b) the sound on/off setting (c) your last game level (d) notes to read offline
19. 19.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
20. 20.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Aman", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Aman (c) Zoya
21. 21.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Monsoon", "Stars", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Ocean (c) Monsoon (d) Sunrise
22. 22.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) notes to read offline (d) photos on two devices
23. 23.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
24. 24.Which of these fits saving in the cloud? (a) a draft you are typing (b) photos on two devices (c) your last game level (d) the sound on/off setting
25. 25.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
26. 26.💾 Where should the app save photos on two devices: 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 = ["Kites", "Ocean"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
28. 28.💾 In most code, the first item of a list is at position ___. (a) 1 (b) 2 (c) 0 (d) 10
29. 29.True or false: your last game level fits saving in the cloud. (a) False (b) True
30. 30.💾 What number does this code show?
    let points = 5;
    points = points - 2;
    points = points + 5;
    show(points);
31. 31.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud backup (d) a cloud leaderboard
32. 32.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) never need a password (c) shrink the app (d) use it on any device
33. 33.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Zoya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Aman (c) Kabir
34. 34.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
35. 35.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Monsoon", "Rain", "Stars"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Stars (c) Monsoon (d) Rain
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Kites", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Stars (c) Monsoon
37. 37.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
38. 38.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
39. 39.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 1;
    show(score);
40. 40.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Kabir (c) Meera

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