App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 104 · 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) photos on two devices (b) a shared to-do list (c) a class leaderboard (d) notes to read offline
2. 2.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
3. 3.💾 What number does this code show?
   let songs = ["Rain", "Kites", "Stars"];
   songs.push("Ocean");
   songs.push("Monsoon");
   show(songs.length);
4. 4.💾 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
5. 5.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Meera", "Arjun", "Zoya"];
   show(friends[2]); (a) Riya (b) Zoya (c) Meera (d) Arjun
6. 6.Which of these fits saving on the phone? (a) photos on two devices (b) your last game level (c) a class leaderboard (d) chat messages to friends
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.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) never need a password (c) use it on any device (d) skip the internet
9. 9.💾 In most code, the first item of a list is at position ___. (a) 0 (b) 2 (c) 10 (d) 1
10. 10.Which of these fits saving on the phone? (a) a shared to-do list (b) chat messages to friends (c) the sound on/off setting (d) photos on two devices
11. 11.💾 What number does this code show?
    let lives = 5;
    lives = lives - 2;
    lives = lives + 4;
    show(lives);
12. 12.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Science", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Music (c) Science
13. 13.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
14. 14.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
15. 15.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Stars", "Kites"];
    show(songs[1]); (a) Monsoon (b) Kites (c) Stars
16. 16.💾 What number does this code show?
    let score = 5;
    score = score - 5;
    score = score + 2;
    show(score);
17. 17.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
18. 18.Which of these fits saving in the cloud? (a) a draft you are typing (b) a class leaderboard (c) notes to read offline (d) the sound on/off setting
19. 19.💾 What is a variable? (a) a named box for a value (b) a picture (c) a phone setting (d) a type of screen
20. 20.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
21. 21.💾 What number does this code show?
    let points = 7;
    points = points - 4;
    points = points + 1;
    show(points);
22. 22.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
23. 23.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Science", "Music"];
    show(notes[1]); (a) Music (b) Maths (c) Science
24. 24.True or false: a shared to-do list fits saving in the cloud. (a) True (b) False
25. 25.💾 What number does this code show?
    let notes = ["Hindi", "Art", "Maths", "Science"];
    notes.push("Music");
    notes.push("Sports");
    show(notes.length);
26. 26.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
27. 27.Which of these fits saving in the cloud? (a) chat messages to friends (b) the sound on/off setting (c) your last game level (d) a draft you are typing
28. 28.💾 What number does this code show?
    let points = 7;
    points = points - 4;
    points = points + 5;
    show(points);
29. 29.💾 What number does this code show?
    let friends = ["Aman", "Zoya", "Riya", "Arjun"];
    friends.push("Meera");
    friends.push("Kabir");
    show(friends.length);
30. 30.💾 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
31. 31.💾 What number does this code show?
    let songs = ["Sunrise", "Stars"];
    songs.push("Kites");
    songs.push("Rain");
    show(songs.length);
32. 32.💾 What number does this code show?
    let points = 6;
    points = points - 1;
    points = points + 1;
    show(points);
33. 33.💾 What number does this code show?
    let notes = ["Music", "Hindi", "Art", "Sports"];
    notes.push("Maths");
    notes.push("Science");
    show(notes.length);
34. 34.💾 What number does this code show?
    let friends = ["Meera", "Riya", "Arjun", "Aman"];
    friends.push("Zoya");
    show(friends.length);
35. 35.💾 What number does this code show?
    let notes = ["Sports", "Music", "Maths"];
    notes.push("Art");
    show(notes.length);
36. 36.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Aman", "Riya", "Kabir", "Arjun"];
    show(friends[0]); (a) Kabir (b) Riya (c) Aman (d) Zoya
37. 37.💾 What number does this code show?
    let points = 5;
    points = points - 3;
    points = points + 4;
    show(points);
38. 38.💾 What does this code show? (Positions start at 0.)
    let notes = ["Science", "Music", "Maths", "Sports", "Hindi"];
    show(notes[0]); (a) Music (b) Sports (c) Maths (d) Science
39. 39.💾 What number does this code show?
    let notes = ["Sports", "Music", "Hindi", "Science"];
    notes.push("Maths");
    notes.push("Art");
    show(notes.length);
40. 40.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Kabir", "Riya"];
    show(friends[1]); (a) Kabir (b) Riya (c) Arjun

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