App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 627 · 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 class leaderboard (b) chat messages to friends (c) notes to read offline (d) photos on two devices
2. 2.Which of these fits saving on the phone? (a) the sound on/off setting (b) chat messages to friends (c) a class leaderboard (d) photos on two devices
3. 3.💾 What number does this code show?
   let stars = 4;
   stars = stars - 1;
   stars = stars + 2;
   show(stars);
4. 4.💾 What is a variable? (a) a phone setting (b) a picture (c) a named box for a value (d) a type of screen
5. 5.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) chat messages to friends (d) the sound on/off setting
6. 6.💾 What does this code show? (Positions start at 0.)
   let friends = ["Aman", "Kabir", "Riya", "Zoya"];
   show(friends[2]); (a) Riya (b) Zoya (c) Aman (d) Kabir
7. 7.💾 pop() takes off the last item. What does this code show?
   let notes = ["Music", "Sports", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Music (b) Sports (c) Art
8. 8.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
9. 9.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
10. 10.True or false: notes to read offline fits saving on the phone. (a) False (b) True
11. 11.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 10 (c) 2 (d) 1
12. 12.💾 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
13. 13.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
14. 14.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
15. 15.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
16. 16.💾 What number does this code show?
    let notes = ["Science", "Music", "Sports", "Hindi"];
    notes.push("Art");
    notes.push("Maths");
    show(notes.length);
17. 17.💾 Saving data in the cloud lets you ___. (a) never need a password (b) use it on any device (c) skip the internet (d) shrink the app
18. 18.💾 What number does this code show?
    let score = 8;
    score = score - 7;
    score = score + 4;
    show(score);
19. 19.True or false: your last game level fits saving on the phone. (a) False (b) True
20. 20.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) in the cloud (b) on the phone
21. 21.💾 What number does this code show?
    let songs = ["Stars", "Kites", "Sunrise", "Ocean"];
    songs.push("Monsoon");
    show(songs.length);
22. 22.💾 What number does this code show?
    let friends = ["Meera", "Aman", "Kabir", "Riya"];
    friends.push("Zoya");
    show(friends.length);
23. 23.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
24. 24.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Ocean", "Monsoon", "Sunrise"];
    show(songs[1]); (a) Monsoon (b) Sunrise (c) Ocean (d) Kites
25. 25.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Science"];
    show(notes[0]); (a) Art (b) Maths (c) Science
26. 26.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Sports", "Art", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Sports (c) Maths (d) Art
27. 27.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Riya", "Kabir", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Kabir (c) Riya (d) Aman
28. 28.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Ocean", "Stars", "Sunrise", "Monsoon"];
    show(songs[2]); (a) Ocean (b) Sunrise (c) Stars (d) Kites
29. 29.💾 What number does this code show?
    let notes = ["Science", "Art", "Sports", "Hindi"];
    notes.push("Maths");
    show(notes.length);
30. 30.💾 Data saved only on the phone is lost when ___. (a) the app is closed (b) the screen turns off (c) you send a message (d) the phone is lost
31. 31.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
32. 32.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Music", "Hindi", "Art", "Science"];
    show(notes[3]); (a) Maths (b) Art (c) Music (d) Hindi
33. 33.True or false: your last game level fits saving in the cloud. (a) False (b) True
34. 34.💾 What number does this code show?
    let coins = 8;
    coins = coins - 5;
    coins = coins + 3;
    show(coins);
35. 35.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Kites", "Sunrise", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Kites (c) Rain (d) Sunrise
36. 36.💾 What number does this code show?
    let friends = ["Arjun", "Zoya", "Meera", "Kabir"];
    friends.push("Aman");
    friends.push("Riya");
    show(friends.length);
37. 37.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a shared to-do list (d) a draft you are typing
38. 38.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Zoya", "Kabir"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Zoya (c) Arjun
39. 39.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
40. 40.💾 What number does this code show?
    let coins = 4;
    coins = coins - 4;
    coins = coins + 5;
    show(coins);

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