App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 718 · 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 number does this code show?
   let stars = 7;
   stars = stars - 1;
   stars = stars + 5;
   show(stars);
2. 2.💾 pop() takes off the last item. What does this code show?
   let songs = ["Monsoon", "Rain", "Kites", "Ocean"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Rain (b) Kites (c) Ocean (d) Monsoon
3. 3.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
4. 4.💾 What number does this code show?
   let friends = ["Meera", "Zoya", "Riya", "Arjun"];
   friends.push("Aman");
   friends.push("Kabir");
   show(friends.length);
5. 5.True or false: your last game level fits saving in the cloud. (a) False (b) True
6. 6.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
7. 7.💾 What number does this code show?
   let songs = ["Kites", "Rain", "Sunrise"];
   songs.push("Ocean");
   songs.push("Monsoon");
   show(songs.length);
8. 8.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
9. 9.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Music", "Hindi", "Art"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Hindi (b) Science (c) Music (d) Art
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Ocean", "Rain", "Kites", "Stars"];
    show(songs[2]); (a) Stars (b) Ocean (c) Rain (d) Kites
11. 11.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
12. 12.Which of these fits saving in the cloud? (a) a class leaderboard (b) a draft you are typing (c) notes to read offline (d) the sound on/off setting
13. 13.Which of these fits saving on the phone? (a) a class leaderboard (b) a draft you are typing (c) a shared to-do list (d) photos on two devices
14. 14.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
15. 15.💾 What number does this code show?
    let score = 6;
    score = score - 4;
    score = score + 5;
    show(score);
16. 16.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Maths", "Music", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Science (c) Music (d) Hindi
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Art", "Science", "Music"];
    show(notes[1]); (a) Science (b) Music (c) Art
18. 18.💾 Which can hold many values in order? (a) a list (b) a switch (c) a button (d) a single number
19. 19.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) chat messages to friends (d) notes to read offline
20. 20.True or false: photos on two devices fits saving on the phone. (a) False (b) True
21. 21.Which of these fits saving on the phone? (a) chat messages to friends (b) the sound on/off setting (c) a class leaderboard (d) photos on two devices
22. 22.💾 What is a variable? (a) a type of screen (b) a picture (c) a named box for a value (d) a phone setting
23. 23.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
24. 24.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) photos on two devices (d) your last game level
25. 25.💾 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
26. 26.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
27. 27.💾 What number does this code show?
    let songs = ["Sunrise", "Stars", "Kites"];
    songs.push("Ocean");
    show(songs.length);
28. 28.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Kabir", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Riya (c) Arjun
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Maths", "Music"];
    show(notes[0]); (a) Maths (b) Music (c) Science
30. 30.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a shared to-do list (c) your last game level (d) notes to read offline
31. 31.💾 What number does this code show?
    let friends = ["Riya", "Kabir"];
    friends.push("Aman");
    show(friends.length);
32. 32.💾 What number does this code show?
    let friends = ["Riya", "Zoya", "Arjun"];
    friends.push("Meera");
    show(friends.length);
33. 33.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) photos on two devices (d) chat messages to friends
34. 34.💾 What number does this code show?
    let lives = 3;
    lives = lives - 2;
    lives = lives + 3;
    show(lives);
35. 35.💾 What number does this code show?
    let stars = 6;
    stars = stars - 1;
    stars = stars + 4;
    show(stars);
36. 36.💾 Which works with no internet at all? (a) a shared chat (b) a cloud leaderboard (c) a cloud backup (d) data saved on the phone
37. 37.💾 What number does this code show?
    let stars = 3;
    stars = stars - 1;
    stars = stars + 5;
    show(stars);
38. 38.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Kabir", "Zoya", "Arjun", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Meera (b) Zoya (c) Arjun (d) Kabir
39. 39.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Sports", "Music", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Sports (c) Art (d) Music
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Music", "Hindi", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Music (c) Art (d) Hindi

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