App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 993 · 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 - 2;
   stars = stars + 1;
   show(stars);
2. 2.Which of these fits saving in the cloud? (a) your last game level (b) photos on two devices (c) notes to read offline (d) the sound on/off setting
3. 3.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
4. 4.💾 What number does this code show?
   let songs = ["Rain", "Kites"];
   songs.push("Sunrise");
   show(songs.length);
5. 5.💾 What number does this code show?
   let friends = ["Zoya", "Arjun"];
   friends.push("Meera");
   show(friends.length);
6. 6.💾 What is a variable? (a) a named box for a value (b) a picture (c) a type of screen (d) a phone setting
7. 7.💾 What number does this code show?
   let songs = ["Monsoon", "Rain", "Kites", "Stars"];
   songs.push("Sunrise");
   show(songs.length);
8. 8.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a class leaderboard (d) the sound on/off setting
9. 9.Which of these fits saving in the cloud? (a) a draft you are typing (b) a shared to-do list (c) the sound on/off setting (d) notes to read offline
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Rain", "Stars", "Ocean", "Sunrise"];
    show(songs[0]); (a) Ocean (b) Rain (c) Monsoon (d) Stars
11. 11.True or false: your last game level fits saving in the cloud. (a) False (b) True
12. 12.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
13. 13.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) never need a password (c) shrink the app (d) use it on any device
14. 14.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Science", "Hindi", "Maths", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Hindi (c) Science (d) Music
15. 15.💾 Where should the app save the sound on/off setting: on the phone or in the cloud? (a) in the cloud (b) on the phone
16. 16.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Music", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Art (c) Music (d) Maths
17. 17.💾 Which works with no internet at all? (a) a shared chat (b) a cloud backup (c) a cloud leaderboard (d) data saved on the phone
18. 18.💾 What number does this code show?
    let friends = ["Meera", "Arjun", "Riya"];
    friends.push("Aman");
    show(friends.length);
19. 19.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Meera", "Kabir", "Arjun"];
    show(friends[0]); (a) Riya (b) Meera (c) Kabir (d) Arjun
20. 20.💾 What number does this code show?
    let points = 9;
    points = points - 3;
    points = points + 1;
    show(points);
21. 21.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
22. 22.💾 What number does this code show?
    let lives = 6;
    lives = lives - 3;
    lives = lives + 2;
    show(lives);
23. 23.💾 Data saved only on the phone is lost when ___. (a) the phone is lost (b) the app is closed (c) you send a message (d) the screen turns off
24. 24.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 0 (d) 2
25. 25.Which of these fits saving on the phone? (a) photos on two devices (b) a draft you are typing (c) a shared to-do list (d) a class leaderboard
26. 26.💾 What number does this code show?
    let notes = ["Music", "Maths", "Science", "Hindi"];
    notes.push("Art");
    notes.push("Sports");
    show(notes.length);
27. 27.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Ocean", "Rain"];
    show(songs[0]); (a) Ocean (b) Monsoon (c) Rain
28. 28.💾 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
29. 29.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Hindi", "Art", "Music"];
    show(notes[0]); (a) Art (b) Sports (c) Hindi (d) Music
30. 30.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
31. 31.💾 What number does this code show?
    let score = 7;
    score = score - 7;
    score = score + 5;
    show(score);
32. 32.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Art (d) Music
33. 33.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
34. 34.💾 What number does this code show?
    let stars = 7;
    stars = stars - 7;
    stars = stars + 2;
    show(stars);
35. 35.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Arjun", "Zoya", "Riya"];
    show(friends[1]); (a) Riya (b) Zoya (c) Meera (d) Arjun
37. 37.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
38. 38.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Stars", "Monsoon", "Sunrise"];
    show(songs[1]); (a) Sunrise (b) Monsoon (c) Rain (d) Stars
40. 40.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Science", "Music", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Maths (c) Music (d) Science

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