App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 816 · 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: chat messages to friends fits saving on the phone. (a) True (b) False
2. 2.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
3. 3.💾 What number does this code show?
   let points = 4;
   points = points - 2;
   points = points + 1;
   show(points);
4. 4.💾 What number does this code show?
   let stars = 9;
   stars = stars - 6;
   stars = stars + 2;
   show(stars);
5. 5.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
6. 6.💾 What is a variable? (a) a picture (b) a named box for a value (c) a type of screen (d) a phone setting
7. 7.💾 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
8. 8.💾 What number does this code show?
   let songs = ["Stars", "Monsoon", "Rain"];
   songs.push("Ocean");
   show(songs.length);
9. 9.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
10. 10.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) a class leaderboard (d) your last game level
11. 11.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
12. 12.True or false: photos on two devices fits saving on the phone. (a) False (b) True
13. 13.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Kites", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Sunrise (c) Kites
14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Stars", "Sunrise", "Monsoon", "Ocean"];
    show(songs[3]); (a) Kites (b) Sunrise (c) Stars (d) Monsoon
15. 15.Which of these fits saving in the cloud? (a) a draft you are typing (b) your last game level (c) the sound on/off setting (d) photos on two devices
16. 16.Which of these fits saving on the phone? (a) photos on two devices (b) notes to read offline (c) a shared to-do list (d) chat messages to friends
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Sports"];
    show(notes[0]); (a) Sports (b) Art (c) Maths
18. 18.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Monsoon (c) Stars
19. 19.Which of these fits saving on the phone? (a) the sound on/off setting (b) chat messages to friends (c) a class leaderboard (d) a shared to-do list
20. 20.💾 Which works with no internet at all? (a) a cloud backup (b) a shared chat (c) a cloud leaderboard (d) data saved on the phone
21. 21.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Sunrise", "Stars", "Ocean", "Rain"];
    show(songs[3]); (a) Sunrise (b) Ocean (c) Stars (d) Monsoon
22. 22.💾 pop() takes off the last item. What does this code show?
    let songs = ["Kites", "Ocean", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Kites (b) Ocean (c) Sunrise
23. 23.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
24. 24.💾 What number does this code show?
    let lives = 5;
    lives = lives - 3;
    lives = lives + 3;
    show(lives);
25. 25.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
26. 26.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Kites", "Ocean", "Monsoon"];
    show(songs[1]); (a) Ocean (b) Sunrise (c) Rain (d) Kites
27. 27.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
28. 28.Which of these fits saving in the cloud? (a) a shared to-do list (b) notes to read offline (c) your last game level (d) a draft you are typing
29. 29.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) the sound on/off setting (d) a class leaderboard
30. 30.💾 Where should the app save a draft you are typing: on the phone or in the cloud? (a) on the phone (b) in the cloud
31. 31.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Riya", "Aman", "Arjun"];
    show(friends[1]); (a) Aman (b) Meera (c) Riya (d) Arjun
32. 32.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
33. 33.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Arjun", "Zoya", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Kabir (c) Zoya (d) Riya
34. 34.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 1 (d) 2
35. 35.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Monsoon", "Stars"];
    show(songs[2]); (a) Monsoon (b) Sunrise (c) Stars
36. 36.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Stars", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Monsoon (c) Stars
37. 37.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Rain", "Sunrise", "Monsoon", "Kites"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Monsoon (d) Sunrise
38. 38.💾 What number does this code show?
    let songs = ["Rain", "Ocean"];
    songs.push("Monsoon");
    show(songs.length);
39. 39.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
40. 40.True or false: a class leaderboard fits saving on the phone. (a) False (b) True

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