App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 329 · 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 in the cloud. (a) False (b) True
2. 2.Which of these fits saving on the phone? (a) a shared to-do list (b) the sound on/off setting (c) a class leaderboard (d) chat messages to friends
3. 3.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
4. 4.Which of these fits saving in the cloud? (a) a shared to-do list (b) notes to read offline (c) the sound on/off setting (d) a draft you are typing
5. 5.💾 What does this code show? (Positions start at 0.)
   let friends = ["Arjun", "Kabir", "Riya", "Aman"];
   show(friends[3]); (a) Riya (b) Kabir (c) Aman (d) Arjun
6. 6.Which of these fits saving on the phone? (a) photos on two devices (b) a shared to-do list (c) your last game level (d) a class leaderboard
7. 7.💾 What does this code show? (Positions start at 0.)
   let friends = ["Arjun", "Aman", "Riya"];
   show(friends[2]); (a) Riya (b) Arjun (c) Aman
8. 8.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
9. 9.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
10. 10.True or false: your last game level fits saving in the cloud. (a) True (b) False
11. 11.💾 What number does this code show?
    let points = 4;
    points = points - 2;
    points = points + 1;
    show(points);
12. 12.💾 What number does this code show?
    let songs = ["Rain", "Monsoon", "Ocean", "Kites"];
    songs.push("Stars");
    show(songs.length);
13. 13.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Music", "Sports", "Art"];
    show(notes[0]); (a) Maths (b) Art (c) Music (d) Sports
14. 14.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
15. 15.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) notes to read offline (d) chat messages to friends
16. 16.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
17. 17.💾 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
18. 18.💾 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
19. 19.💾 What number does this code show?
    let coins = 3;
    coins = coins - 2;
    coins = coins + 1;
    show(coins);
20. 20.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) never need a password (d) use it on any device
21. 21.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
22. 22.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Kabir", "Riya", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Riya (d) Zoya
23. 23.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Sports", "Science", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Art (d) Science
24. 24.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Kites", "Stars", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Monsoon (b) Kites (c) Rain (d) Stars
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.💾 Which can hold many values in order? (a) a switch (b) a button (c) a list (d) a single number
27. 27.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
28. 28.💾 What is a variable? (a) a picture (b) a type of screen (c) a named box for a value (d) a phone setting
29. 29.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Maths", "Music", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Sports (c) Maths (d) Music
30. 30.💾 What number does this code show?
    let friends = ["Meera", "Zoya"];
    friends.push("Arjun");
    show(friends.length);
31. 31.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the screen turns off (d) the phone is lost
32. 32.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
33. 33.💾 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
34. 34.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Art", "Maths"];
    show(notes[2]); (a) Sports (b) Art (c) Maths
35. 35.💾 What number does this code show?
    let notes = ["Art", "Maths"];
    notes.push("Science");
    notes.push("Sports");
    show(notes.length);
36. 36.💾 What number does this code show?
    let songs = ["Monsoon", "Ocean", "Kites", "Rain"];
    songs.push("Stars");
    songs.push("Sunrise");
    show(songs.length);
37. 37.💾 What number does this code show?
    let notes = ["Hindi", "Sports"];
    notes.push("Science");
    show(notes.length);
38. 38.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 3;
    show(score);
39. 39.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
40. 40.💾 What number does this code show?
    let stars = 5;
    stars = stars - 3;
    stars = stars + 1;
    show(stars);

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