App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 469 · 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: chat messages to friends fits saving in the cloud. (a) False (b) True
2. 2.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) a class leaderboard (d) the sound on/off setting
3. 3.💾 pop() takes off the last item. What does this code show?
   let friends = ["Riya", "Meera", "Aman", "Zoya", "Kabir"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Riya (b) Aman (c) Meera (d) Zoya
4. 4.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the phone is lost (c) the screen turns off (d) the app is closed
5. 5.💾 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
6. 6.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 0 (d) 2
7. 7.💾 What number does this code show?
   let friends = ["Riya", "Meera", "Zoya"];
   friends.push("Kabir");
   friends.push("Aman");
   show(friends.length);
8. 8.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a draft you are typing (d) chat messages to friends
9. 9.💾 What number does this code show?
   let score = 9;
   score = score - 7;
   score = score + 2;
   show(score);
10. 10.💾 What number does this code show?
    let notes = ["Sports", "Science"];
    notes.push("Maths");
    show(notes.length);
11. 11.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
12. 12.💾 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
13. 13.💾 Which can hold many values in order? (a) a button (b) a switch (c) a single number (d) a list
14. 14.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
15. 15.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Kites", "Stars", "Monsoon"];
    show(songs[0]); (a) Kites (b) Stars (c) Monsoon (d) Rain
16. 16.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) notes to read offline (d) chat messages to friends
17. 17.Which of these fits saving in the cloud? (a) a draft you are typing (b) photos on two devices (c) the sound on/off setting (d) notes to read offline
18. 18.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean", "Stars", "Monsoon"];
    songs.push("Rain");
    songs.push("Kites");
    show(songs.length);
19. 19.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Zoya", "Meera", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Arjun (c) Zoya (d) Meera
21. 21.💾 Which works with no internet at all? (a) a shared chat (b) a cloud backup (c) data saved on the phone (d) a cloud leaderboard
22. 22.💾 What number does this code show?
    let songs = ["Rain", "Stars", "Monsoon", "Ocean"];
    songs.push("Kites");
    show(songs.length);
23. 23.💾 What number does this code show?
    let notes = ["Hindi", "Science", "Music"];
    notes.push("Sports");
    notes.push("Maths");
    show(notes.length);
24. 24.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) photos on two devices (d) a class leaderboard
25. 25.True or false: photos on two devices fits saving on the phone. (a) True (b) False
26. 26.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
28. 28.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) a draft you are typing (d) the sound on/off setting
29. 29.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
30. 30.💾 What number does this code show?
    let lives = 6;
    lives = lives - 2;
    lives = lives + 5;
    show(lives);
31. 31.💾 What number does this code show?
    let friends = ["Zoya", "Riya"];
    friends.push("Aman");
    show(friends.length);
32. 32.💾 What is a variable? (a) a picture (b) a phone setting (c) a type of screen (d) a named box for a value
33. 33.💾 What number does this code show?
    let points = 4;
    points = points - 4;
    points = points + 4;
    show(points);
34. 34.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
35. 35.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) chat messages to friends (d) a draft you are typing
36. 36.💾 What number does this code show?
    let friends = ["Zoya", "Arjun"];
    friends.push("Kabir");
    show(friends.length);
37. 37.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Arjun", "Zoya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Zoya (c) Aman (d) Arjun
39. 39.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Riya", "Arjun", "Aman"];
    show(friends[2]); (a) Zoya (b) Riya (c) Arjun (d) Aman
40. 40.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) on the phone (b) in the cloud

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