App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 665 · 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.💾 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
2. 2.💾 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
3. 3.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) chat messages to friends (d) notes to read offline
4. 4.💾 What does this code show? (Positions start at 0.)
   let notes = ["Art", "Maths", "Hindi"];
   show(notes[1]); (a) Maths (b) Hindi (c) Art
5. 5.💾 What number does this code show?
   let lives = 7;
   lives = lives - 2;
   lives = lives + 2;
   show(lives);
6. 6.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) a draft you are typing (d) a shared to-do list
7. 7.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) on the phone (b) in the cloud
8. 8.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) chat messages to friends (d) your last game level
9. 9.Which of these fits saving in the cloud? (a) notes to read offline (b) your last game level (c) chat messages to friends (d) the sound on/off setting
10. 10.Which of these fits saving on the phone? (a) a class leaderboard (b) photos on two devices (c) chat messages to friends (d) the sound on/off setting
11. 11.💾 What number does this code show?
    let friends = ["Kabir", "Meera", "Zoya", "Aman"];
    friends.push("Arjun");
    show(friends.length);
12. 12.💾 What number does this code show?
    let score = 7;
    score = score - 5;
    score = score + 2;
    show(score);
13. 13.💾 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
14. 14.💾 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
15. 15.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Kites", "Monsoon", "Stars", "Ocean"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Sunrise (b) Monsoon (c) Kites (d) Stars
16. 16.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Sports", "Maths"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Art (c) Sports (d) Hindi
17. 17.Which of these fits saving in the cloud? (a) a draft you are typing (b) photos on two devices (c) notes to read offline (d) the sound on/off setting
18. 18.💾 What number does this code show?
    let songs = ["Kites", "Ocean"];
    songs.push("Monsoon");
    songs.push("Rain");
    show(songs.length);
19. 19.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
20. 20.💾 What number does this code show?
    let stars = 5;
    stars = stars - 2;
    stars = stars + 5;
    show(stars);
21. 21.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
22. 22.💾 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
23. 23.💾 What does this code show? (Positions start at 0.)
    let friends = ["Kabir", "Zoya", "Riya"];
    show(friends[2]); (a) Kabir (b) Zoya (c) Riya
24. 24.💾 What number does this code show?
    let points = 5;
    points = points - 1;
    points = points + 4;
    show(points);
25. 25.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Sunrise", "Stars", "Monsoon"];
    show(songs[1]); (a) Kites (b) Sunrise (c) Stars (d) Rain
26. 26.True or false: your last game level fits saving on the phone. (a) False (b) True
27. 27.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
28. 28.💾 What number does this code show?
    let notes = ["Art", "Hindi", "Sports"];
    notes.push("Music");
    show(notes.length);
29. 29.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Meera", "Zoya", "Aman", "Kabir"];
    show(friends[4]); (a) Zoya (b) Kabir (c) Meera (d) Riya
30. 30.💾 pop() takes off the last item. What does this code show?
    let songs = ["Stars", "Ocean", "Rain", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Ocean (b) Monsoon (c) Stars (d) Rain
31. 31.💾 What number does this code show?
    let friends = ["Aman", "Riya", "Kabir"];
    friends.push("Zoya");
    show(friends.length);
32. 32.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
33. 33.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 10 (c) 1 (d) 0
34. 34.Which of these fits saving in the cloud? (a) notes to read offline (b) the sound on/off setting (c) a draft you are typing (d) a shared to-do list
35. 35.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
36. 36.True or false: the sound on/off setting fits saving on the phone. (a) False (b) True
37. 37.💾 What is a variable? (a) a type of screen (b) a picture (c) a phone setting (d) a named box for a value
38. 38.💾 pop() takes off the last item. What does this code show?
    let songs = ["Sunrise", "Stars", "Rain"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Rain (c) Sunrise
39. 39.💾 What number does this code show?
    let friends = ["Zoya", "Kabir"];
    friends.push("Meera");
    show(friends.length);
40. 40.💾 What number does this code show?
    let score = 3;
    score = score - 2;
    score = score + 4;
    show(score);

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