App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 250 · 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.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) chat messages to friends (d) notes to read offline
2. 2.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) your last game level (d) a class leaderboard
3. 3.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) chat messages to friends (d) notes to read offline
4. 4.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Aman", "Arjun", "Kabir"];
   show(friends[1]); (a) Kabir (b) Riya (c) Aman (d) Arjun
6. 6.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Monsoon", "Sunrise", "Ocean"];
   show(songs[1]); (a) Ocean (b) Monsoon (c) Sunrise (d) Kites
7. 7.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
8. 8.💾 What number does this code show?
   let notes = ["Music", "Maths"];
   notes.push("Science");
   show(notes.length);
9. 9.Which of these fits saving on the phone? (a) a draft you are typing (b) photos on two devices (c) a class leaderboard (d) a shared to-do list
10. 10.True or false: your last game level fits saving in the cloud. (a) True (b) False
11. 11.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Riya", "Aman", "Kabir", "Arjun"];
    show(friends[0]); (a) Riya (b) Aman (c) Zoya (d) Kabir
12. 12.💾 What number does this code show?
    let score = 9;
    score = score - 2;
    score = score + 5;
    show(score);
13. 13.True or false: photos on two devices fits saving on the phone. (a) False (b) True
14. 14.💾 Which can hold many values in order? (a) a switch (b) a button (c) a list (d) a single number
15. 15.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 0 (c) 10 (d) 1
16. 16.💾 What number does this code show?
    let friends = ["Meera", "Zoya"];
    friends.push("Arjun");
    friends.push("Riya");
    show(friends.length);
17. 17.💾 What is a variable? (a) a picture (b) a type of screen (c) a phone setting (d) a named box for a value
18. 18.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) skip the internet (d) use it on any device
19. 19.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
20. 20.True or false: notes to read offline fits saving on the phone. (a) False (b) True
21. 21.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Monsoon", "Rain", "Stars", "Kites"];
    show(songs[2]); (a) Monsoon (b) Stars (c) Sunrise (d) Rain
22. 22.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Kites", "Monsoon"];
    show(songs[0]); (a) Kites (b) Monsoon (c) Ocean
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Hindi"];
    show(notes[1]); (a) Sports (b) Music (c) Hindi
24. 24.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
25. 25.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
26. 26.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
27. 27.💾 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
28. 28.True or false: your last game level fits saving on the phone. (a) False (b) True
29. 29.💾 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
30. 30.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
31. 31.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Rain", "Kites", "Monsoon", "Stars"];
    show(songs[2]); (a) Ocean (b) Monsoon (c) Rain (d) Kites
32. 32.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
33. 33.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
34. 34.💾 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
35. 35.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Maths (c) Sports
36. 36.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) photos on two devices (d) your last game level
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Art", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Music (c) Maths
38. 38.💾 What number does this code show?
    let songs = ["Ocean", "Kites"];
    songs.push("Monsoon");
    songs.push("Sunrise");
    show(songs.length);
39. 39.💾 Which works with no internet at all? (a) a cloud leaderboard (b) data saved on the phone (c) a shared chat (d) a cloud backup
40. 40.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Aman", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Meera (c) Aman

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