App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 201 · 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.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Art", "Hindi"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Science (b) Hindi (c) Art
2. 2.💾 What number does this code show?
   let coins = 3;
   coins = coins - 3;
   coins = coins + 4;
   show(coins);
3. 3.💾 Where should the app save a draft you are typing: 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 = ["Monsoon", "Kites", "Rain", "Sunrise"];
   songs.push("Stars");
   songs.push("Ocean");
   show(songs.length);
5. 5.💾 What does this code show? (Positions start at 0.)
   let friends = ["Riya", "Aman", "Kabir", "Meera", "Zoya"];
   show(friends[2]); (a) Aman (b) Meera (c) Riya (d) Kabir
6. 6.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
7. 7.💾 What does this code show? (Positions start at 0.)
   let songs = ["Rain", "Monsoon", "Sunrise"];
   show(songs[1]); (a) Sunrise (b) Monsoon (c) Rain
8. 8.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
9. 9.Which of these fits saving in the cloud? (a) a shared to-do list (b) notes to read offline (c) a draft you are typing (d) your last game level
10. 10.Which of these fits saving on the phone? (a) a shared to-do list (b) your last game level (c) chat messages to friends (d) photos on two devices
11. 11.💾 What number does this code show?
    let stars = 5;
    stars = stars - 1;
    stars = stars + 3;
    show(stars);
12. 12.Which of these fits saving in the cloud? (a) the sound on/off setting (b) notes to read offline (c) a draft you are typing (d) photos on two devices
13. 13.💾 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
14. 14.Which of these fits saving on the phone? (a) photos on two devices (b) a class leaderboard (c) notes to read offline (d) a shared to-do list
15. 15.True or false: a draft you are typing fits saving on the phone. (a) True (b) False
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Meera", "Aman", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Meera (c) Aman
17. 17.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) data saved on the phone (d) a shared chat
18. 18.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
19. 19.💾 What number does this code show?
    let notes = ["Sports", "Music", "Science", "Maths"];
    notes.push("Hindi");
    show(notes.length);
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Maths (d) Sports
21. 21.💾 What number does this code show?
    let notes = ["Hindi", "Maths", "Science", "Music"];
    notes.push("Art");
    notes.push("Sports");
    show(notes.length);
22. 22.💾 What number does this code show?
    let points = 5;
    points = points - 2;
    points = points + 2;
    show(points);
23. 23.💾 What number does this code show?
    let notes = ["Music", "Art", "Science", "Maths"];
    notes.push("Hindi");
    notes.push("Sports");
    show(notes.length);
24. 24.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a picture (d) a type of screen
25. 25.True or false: chat messages to friends fits saving in the cloud. (a) True (b) False
26. 26.💾 Saving data in the cloud lets you ___. (a) never need a password (b) skip the internet (c) shrink the app (d) use it on any device
27. 27.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the app is closed (c) the screen turns off (d) the phone is lost
28. 28.Which of these fits saving in the cloud? (a) a class leaderboard (b) the sound on/off setting (c) notes to read offline (d) your last game level
29. 29.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
30. 30.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
31. 31.True or false: photos on two devices fits saving on the phone. (a) True (b) False
32. 32.💾 What number does this code show?
    let score = 6;
    score = score - 6;
    score = score + 2;
    show(score);
33. 33.💾 What number does this code show?
    let songs = ["Stars", "Monsoon", "Kites", "Sunrise"];
    songs.push("Ocean");
    show(songs.length);
34. 34.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
35. 35.💾 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
36. 36.💾 What does this code show? (Positions start at 0.)
    let notes = ["Music", "Sports", "Maths"];
    show(notes[1]); (a) Sports (b) Music (c) Maths
37. 37.💾 What number does this code show?
    let notes = ["Science", "Sports", "Art"];
    notes.push("Maths");
    show(notes.length);
38. 38.💾 Which can hold many values in order? (a) a switch (b) a single number (c) a list (d) a button
39. 39.Which of these fits saving on the phone? (a) a draft you are typing (b) chat messages to friends (c) a class leaderboard (d) a shared to-do list
40. 40.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True

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