App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 52 · 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.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) shrink the app (d) use it on any device
2. 2.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.💾 What number does this code show?
   let stars = 4;
   stars = stars - 2;
   stars = stars + 3;
   show(stars);
4. 4.Which of these fits saving in the cloud? (a) a class leaderboard (b) the sound on/off setting (c) your last game level (d) notes to read offline
5. 5.💾 What number does this code show?
   let friends = ["Arjun", "Riya"];
   friends.push("Meera");
   friends.push("Aman");
   show(friends.length);
6. 6.💾 What number does this code show?
   let stars = 7;
   stars = stars - 5;
   stars = stars + 3;
   show(stars);
7. 7.True or false: photos on two devices fits saving on the phone. (a) True (b) False
8. 8.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the screen turns off (c) you send a message (d) the app is closed
9. 9.💾 What number does this code show?
   let friends = ["Arjun", "Aman"];
   friends.push("Riya");
   show(friends.length);
10. 10.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
11. 11.True or false: your last game level fits saving in the cloud. (a) False (b) True
12. 12.💾 Which can hold many values in order? (a) a switch (b) a list (c) a single number (d) a button
13. 13.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
15. 15.💾 What number does this code show?
    let notes = ["Hindi", "Science", "Maths", "Art"];
    notes.push("Music");
    notes.push("Sports");
    show(notes.length);
16. 16.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Stars", "Monsoon", "Ocean", "Rain"];
    show(songs[3]); (a) Monsoon (b) Sunrise (c) Ocean (d) Stars
17. 17.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 1;
    show(score);
18. 18.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
19. 19.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Hindi", "Maths", "Science"];
    show(notes[1]); (a) Hindi (b) Art (c) Maths (d) Science
20. 20.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
21. 21.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Hindi", "Science", "Sports", "Art"];
    show(notes[0]); (a) Sports (b) Hindi (c) Music (d) Science
22. 22.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) photos on two devices (d) the sound on/off setting
23. 23.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
24. 24.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Kites"];
    show(songs[0]); (a) Monsoon (b) Kites (c) Rain
25. 25.💾 What is a variable? (a) a type of screen (b) a phone setting (c) a picture (d) a named box for a value
26. 26.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
27. 27.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Sports"];
    show(notes[0]); (a) Music (b) Sports (c) Science
28. 28.💾 What number does this code show?
    let notes = ["Maths", "Hindi", "Sports", "Art"];
    notes.push("Music");
    show(notes.length);
29. 29.True or false: notes to read offline fits saving on the phone. (a) True (b) False
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Rain", "Kites", "Monsoon", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Rain (c) Monsoon (d) Sunrise
31. 31.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
32. 32.💾 What number does this code show?
    let notes = ["Hindi", "Art", "Maths"];
    notes.push("Sports");
    show(notes.length);
33. 33.💾 What number does this code show?
    let friends = ["Zoya", "Riya"];
    friends.push("Arjun");
    friends.push("Aman");
    show(friends.length);
34. 34.💾 Which works with no internet at all? (a) a shared chat (b) a cloud leaderboard (c) a cloud backup (d) data saved on the phone
35. 35.💾 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
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Riya", "Aman", "Meera", "Arjun"];
    show(friends[0]); (a) Kabir (b) Riya (c) Aman (d) Meera
37. 37.Which of these fits saving on the phone? (a) photos on two devices (b) the sound on/off setting (c) chat messages to friends (d) a class leaderboard
38. 38.💾 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
39. 39.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Hindi", "Science", "Art"];
    show(notes[0]); (a) Science (b) Art (c) Maths (d) Hindi
40. 40.Which of these fits saving on the phone? (a) notes to read offline (b) a shared to-do list (c) photos on two devices (d) a class leaderboard

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