App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 294 · 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 does this code show? (Positions start at 0.)
   let songs = ["Rain", "Ocean", "Kites", "Monsoon"];
   show(songs[3]); (a) Rain (b) Ocean (c) Monsoon (d) Kites
2. 2.💾 What number does this code show?
   let score = 3;
   score = score - 2;
   score = score + 5;
   show(score);
3. 3.True or false: notes to read offline fits saving on the phone. (a) True (b) False
4. 4.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) the sound on/off setting (d) photos on two devices
5. 5.💾 Saving data in the cloud lets you ___. (a) never need a password (b) shrink the app (c) use it on any device (d) skip the internet
6. 6.True or false: a class leaderboard fits saving on the phone. (a) False (b) True
7. 7.💾 pop() takes off the last item. What does this code show?
   let friends = ["Aman", "Meera", "Riya", "Zoya", "Kabir"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Riya (b) Aman (c) Meera (d) Zoya
8. 8.Which of these fits saving on the phone? (a) the sound on/off setting (b) a shared to-do list (c) photos on two devices (d) chat messages to friends
9. 9.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
10. 10.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 3;
    show(score);
11. 11.True or false: photos on two devices fits saving on the phone. (a) True (b) False
12. 12.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
13. 13.💾 What number does this code show?
    let friends = ["Kabir", "Riya", "Meera"];
    friends.push("Arjun");
    show(friends.length);
14. 14.💾 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
15. 15.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
16. 16.💾 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
17. 17.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
18. 18.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Zoya"];
    show(friends[2]); (a) Riya (b) Zoya (c) Arjun
19. 19.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
20. 20.💾 What number does this code show?
    let notes = ["Maths", "Sports"];
    notes.push("Science");
    show(notes.length);
21. 21.💾 Which can hold many values in order? (a) a single number (b) a list (c) a switch (d) a button
22. 22.💾 What is a variable? (a) a named box for a value (b) a type of screen (c) a picture (d) a phone setting
23. 23.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) chat messages to friends (d) a draft you are typing
24. 24.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Meera", "Zoya"];
    show(friends[2]); (a) Zoya (b) Meera (c) Riya
25. 25.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Music", "Science", "Art", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Science (c) Music (d) Art
26. 26.💾 What number does this code show?
    let points = 5;
    points = points - 1;
    points = points + 3;
    show(points);
27. 27.Which of these fits saving on the phone? (a) a shared to-do list (b) notes to read offline (c) a class leaderboard (d) chat messages to friends
28. 28.True or false: chat messages to friends fits saving on the phone. (a) True (b) False
29. 29.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
30. 30.💾 What number does this code show?
    let points = 3;
    points = points - 3;
    points = points + 1;
    show(points);
31. 31.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
32. 32.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) a class leaderboard
33. 33.💾 Which works with no internet at all? (a) a shared chat (b) data saved on the phone (c) a cloud backup (d) a cloud leaderboard
34. 34.💾 pop() takes off the last item. What does this code show?
    let songs = ["Monsoon", "Kites", "Ocean", "Sunrise"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Kites (c) Ocean (d) Monsoon
35. 35.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Riya", "Meera"];
    show(friends[2]); (a) Arjun (b) Meera (c) Riya
36. 36.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Aman", "Meera", "Riya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Riya (c) Meera (d) Aman
37. 37.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a class leaderboard (d) your last game level
38. 38.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Monsoon", "Kites", "Ocean"];
    show(songs[0]); (a) Rain (b) Monsoon (c) Kites (d) Sunrise
39. 39.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Science", "Sports", "Hindi", "Maths"];
    show(notes[3]); (a) Music (b) Sports (c) Hindi (d) Science
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Riya", "Kabir"];
    show(friends[0]); (a) Zoya (b) Riya (c) Kabir

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