App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 49 · 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.💾 What number does this code show?
   let friends = ["Meera", "Kabir"];
   friends.push("Zoya");
   show(friends.length);
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.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) your last game level (d) photos on two devices
4. 4.💾 What is a variable? (a) a type of screen (b) a picture (c) a named box for a value (d) a phone setting
5. 5.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
6. 6.💾 What does this code show? (Positions start at 0.)
   let notes = ["Hindi", "Art", "Science", "Music"];
   show(notes[0]); (a) Music (b) Hindi (c) Art (d) Science
7. 7.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
8. 8.Which of these fits saving in the cloud? (a) notes to read offline (b) a class leaderboard (c) the sound on/off setting (d) a draft you are typing
9. 9.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
10. 10.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Meera", "Arjun", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Kabir (c) Arjun (d) Riya
11. 11.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a button (d) a list
12. 12.💾 What number does this code show?
    let score = 5;
    score = score - 2;
    score = score + 4;
    show(score);
13. 13.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
14. 14.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
15. 15.💾 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
16. 16.Which of these fits saving in the cloud? (a) notes to read offline (b) chat messages to friends (c) a draft you are typing (d) your last game level
17. 17.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the app is closed (c) the screen turns off (d) you send a message
18. 18.💾 What number does this code show?
    let friends = ["Kabir", "Riya", "Arjun"];
    friends.push("Zoya");
    show(friends.length);
19. 19.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) photos on two devices (d) a class leaderboard
20. 20.💾 What number does this code show?
    let songs = ["Sunrise", "Rain", "Monsoon"];
    songs.push("Ocean");
    show(songs.length);
21. 21.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Stars", "Rain", "Ocean"];
    show(songs[0]); (a) Stars (b) Ocean (c) Rain (d) Sunrise
22. 22.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
23. 23.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) your last game level
24. 24.True or false: notes to read offline fits saving on the phone. (a) False (b) True
25. 25.True or false: your last game level fits saving in the cloud. (a) True (b) False
26. 26.Which of these fits saving on the phone? (a) a shared to-do list (b) the sound on/off setting (c) photos on two devices (d) a class leaderboard
27. 27.💾 What number does this code show?
    let songs = ["Ocean", "Stars", "Monsoon", "Sunrise"];
    songs.push("Rain");
    show(songs.length);
28. 28.True or false: photos on two devices fits saving on the phone. (a) False (b) True
29. 29.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
30. 30.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) your last game level (d) a shared to-do list
31. 31.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Monsoon", "Kites", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Kites (c) Sunrise (d) Monsoon
32. 32.💾 What number does this code show?
    let score = 6;
    score = score - 1;
    score = score + 4;
    show(score);
33. 33.💾 What number does this code show?
    let score = 6;
    score = score - 2;
    score = score + 2;
    show(score);
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.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
36. 36.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
37. 37.💾 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
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 = ["Art", "Music", "Science", "Sports", "Hindi"];
    show(notes[3]); (a) Science (b) Music (c) Sports (d) Art
40. 40.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Maths", "Science"];
    show(notes[1]); (a) Art (b) Maths (c) Science

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