App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 761 · 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.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.True or false: photos on two devices fits saving on the phone. (a) False (b) True
3. 3.💾 What does this code show? (Positions start at 0.)
   let friends = ["Kabir", "Meera", "Aman", "Riya", "Arjun"];
   show(friends[4]); (a) Kabir (b) Meera (c) Arjun (d) Aman
4. 4.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
5. 5.True or false: your last game level fits saving in the cloud. (a) True (b) False
6. 6.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) a draft you are typing (d) photos on two devices
7. 7.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
8. 8.💾 Which can hold many values in order? (a) a list (b) a switch (c) a single number (d) a button
9. 9.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
10. 10.💾 Which works with no internet at all? (a) data saved on the phone (b) a shared chat (c) a cloud backup (d) a cloud leaderboard
11. 11.💾 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
12. 12.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the app is closed (c) you send a message (d) the phone is lost
13. 13.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Sports", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Sports (c) Music
14. 14.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Arjun", "Zoya", "Meera", "Aman"];
    show(friends[2]); (a) Kabir (b) Meera (c) Arjun (d) Zoya
15. 15.💾 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
16. 16.💾 What number does this code show?
    let friends = ["Kabir", "Meera", "Riya"];
    friends.push("Zoya");
    show(friends.length);
17. 17.💾 What number does this code show?
    let points = 7;
    points = points - 2;
    points = points + 5;
    show(points);
18. 18.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
19. 19.True or false: your last game level fits saving on the phone. (a) False (b) True
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Maths", "Hindi"];
    show(notes[1]); (a) Science (b) Maths (c) Hindi (d) Art
21. 21.💾 What number does this code show?
    let songs = ["Kites", "Ocean", "Stars"];
    songs.push("Rain");
    show(songs.length);
22. 22.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 1;
    show(score);
23. 23.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) the sound on/off setting (d) notes to read offline
24. 24.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Art", "Maths", "Sports"];
    show(notes[3]); (a) Hindi (b) Sports (c) Art (d) Maths
25. 25.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Meera", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Riya (c) Kabir
26. 26.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 2 (c) 1 (d) 0
27. 27.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Kites", "Sunrise"];
    show(songs[2]); (a) Sunrise (b) Rain (c) Kites
28. 28.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Arjun", "Zoya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Kabir (c) Zoya (d) Aman
29. 29.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) use it on any device (c) skip the internet (d) never need a password
30. 30.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 2;
    show(score);
31. 31.💾 What number does this code show?
    let songs = ["Stars", "Kites", "Sunrise"];
    songs.push("Ocean");
    songs.push("Rain");
    show(songs.length);
32. 32.💾 What number does this code show?
    let notes = ["Science", "Sports", "Art"];
    notes.push("Music");
    show(notes.length);
33. 33.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Aman", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Aman (c) Arjun
34. 34.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Sports", "Maths", "Art", "Science"];
    show(notes[0]); (a) Maths (b) Art (c) Sports (d) Music
35. 35.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Hindi", "Music"];
    show(notes[1]); (a) Maths (b) Music (c) Hindi
36. 36.💾 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
37. 37.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.Which of these fits saving in the cloud? (a) a class leaderboard (b) your last game level (c) notes to read offline (d) a draft you are typing
39. 39.💾 What number does this code show?
    let notes = ["Music", "Sports"];
    notes.push("Maths");
    show(notes.length);
40. 40.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) photos on two devices (d) a shared to-do list

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