App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 486 · 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 is a variable? (a) a named box for a value (b) a picture (c) a phone setting (d) a type of screen
2. 2.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
4. 4.Which of these fits saving in the cloud? (a) a shared to-do list (b) your last game level (c) a draft you are typing (d) the sound on/off setting
5. 5.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 10 (c) 0 (d) 1
6. 6.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) chat messages to friends (d) your last game level
7. 7.💾 What number does this code show?
   let songs = ["Sunrise", "Stars"];
   songs.push("Rain");
   show(songs.length);
8. 8.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
9. 9.💾 What number does this code show?
   let stars = 4;
   stars = stars - 3;
   stars = stars + 1;
   show(stars);
10. 10.True or false: your last game level fits saving in the cloud. (a) False (b) True
11. 11.💾 What number does this code show?
    let notes = ["Maths", "Science"];
    notes.push("Sports");
    notes.push("Hindi");
    show(notes.length);
12. 12.💾 Which can hold many values in order? (a) a list (b) a button (c) a switch (d) a single number
13. 13.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Zoya", "Meera", "Aman", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Zoya (c) Meera (d) Arjun
14. 14.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 1;
    show(stars);
15. 15.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
16. 16.💾 What number does this code show?
    let songs = ["Sunrise", "Ocean", "Rain", "Kites"];
    songs.push("Monsoon");
    show(songs.length);
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Maths", "Art", "Hindi"];
    show(notes[0]); (a) Art (b) Music (c) Hindi (d) Maths
18. 18.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Kabir", "Riya"];
    show(friends[0]); (a) Riya (b) Kabir (c) Meera
19. 19.💾 Saving data in the cloud lets you ___. (a) use it on any device (b) skip the internet (c) shrink the app (d) never need a password
20. 20.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Meera", "Arjun", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Arjun (c) Meera (d) Riya
21. 21.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Music", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Sports (c) Music
22. 22.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
23. 23.💾 What number does this code show?
    let friends = ["Riya", "Zoya", "Kabir", "Meera"];
    friends.push("Arjun");
    friends.push("Aman");
    show(friends.length);
24. 24.💾 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
25. 25.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
26. 26.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Arjun", "Aman", "Riya"];
    show(friends[0]); (a) Riya (b) Meera (c) Aman (d) Arjun
27. 27.💾 What number does this code show?
    let score = 3;
    score = score - 1;
    score = score + 1;
    show(score);
28. 28.💾 What number does this code show?
    let notes = ["Hindi", "Art", "Music", "Sports"];
    notes.push("Maths");
    show(notes.length);
29. 29.Which of these fits saving on the phone? (a) chat messages to friends (b) photos on two devices (c) notes to read offline (d) a shared to-do list
30. 30.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
31. 31.💾 What number does this code show?
    let notes = ["Science", "Maths", "Sports"];
    notes.push("Art");
    show(notes.length);
32. 32.💾 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
33. 33.💾 What number does this code show?
    let coins = 7;
    coins = coins - 4;
    coins = coins + 1;
    show(coins);
34. 34.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud leaderboard (c) a cloud backup (d) a shared chat
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Sports", "Maths", "Art", "Science"];
    show(notes[3]); (a) Hindi (b) Art (c) Sports (d) Maths
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Rain", "Stars", "Monsoon", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Rain (c) Kites (d) Monsoon
37. 37.💾 What does this code show? (Positions start at 0.)
    let friends = ["Aman", "Kabir", "Zoya"];
    show(friends[0]); (a) Kabir (b) Zoya (c) Aman
38. 38.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) a shared to-do list (d) the sound on/off setting
39. 39.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
40. 40.💾 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

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