App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 274 · 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 in the cloud? (a) chat messages to friends (b) your last game level (c) notes to read offline (d) the sound on/off setting
2. 2.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
3. 3.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
4. 4.Which of these fits saving on the phone? (a) the sound on/off setting (b) a shared to-do list (c) a class leaderboard (d) photos on two devices
5. 5.💾 pop() takes off the last item. What does this code show?
   let songs = ["Sunrise", "Rain", "Ocean", "Kites", "Stars"];
   songs.pop();
   show(songs[songs.length - 1]); (a) Ocean (b) Rain (c) Sunrise (d) Kites
6. 6.💾 What number does this code show?
   let friends = ["Kabir", "Zoya"];
   friends.push("Arjun");
   friends.push("Riya");
   show(friends.length);
7. 7.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 1 (c) 10 (d) 0
8. 8.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) on the phone (b) in the cloud
9. 9.💾 What does this code show? (Positions start at 0.)
   let friends = ["Arjun", "Riya", "Zoya", "Aman", "Meera"];
   show(friends[1]); (a) Zoya (b) Aman (c) Arjun (d) Riya
10. 10.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
11. 11.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Kabir", "Riya", "Meera", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Zoya (b) Riya (c) Meera (d) Kabir
12. 12.💾 What number does this code show?
    let notes = ["Art", "Maths", "Hindi", "Sports"];
    notes.push("Science");
    notes.push("Music");
    show(notes.length);
13. 13.💾 What does this code show? (Positions start at 0.)
    let friends = ["Zoya", "Kabir", "Riya"];
    show(friends[0]); (a) Kabir (b) Zoya (c) Riya
14. 14.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Kites", "Monsoon", "Ocean"];
    show(songs[1]); (a) Kites (b) Rain (c) Sunrise (d) Monsoon
15. 15.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
16. 16.💾 What number does this code show?
    let score = 8;
    score = score - 7;
    score = score + 5;
    show(score);
17. 17.💾 What number does this code show?
    let friends = ["Riya", "Arjun", "Kabir"];
    friends.push("Meera");
    friends.push("Aman");
    show(friends.length);
18. 18.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a type of screen (d) a picture
19. 19.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a button (d) a list
20. 20.True or false: notes to read offline fits saving on the phone. (a) True (b) False
21. 21.💾 Which works with no internet at all? (a) a shared chat (b) a cloud backup (c) data saved on the phone (d) a cloud leaderboard
22. 22.💾 What number does this code show?
    let score = 9;
    score = score - 4;
    score = score + 3;
    show(score);
23. 23.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Sunrise", "Monsoon"];
    show(songs[0]); (a) Sunrise (b) Stars (c) Monsoon
24. 24.Which of these fits saving in the cloud? (a) your last game level (b) a shared to-do list (c) a draft you are typing (d) notes to read offline
25. 25.Which of these fits saving on the phone? (a) a draft you are typing (b) a class leaderboard (c) photos on two devices (d) a shared to-do list
26. 26.💾 What number does this code show?
    let notes = ["Art", "Sports", "Science"];
    notes.push("Music");
    show(notes.length);
27. 27.💾 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
28. 28.💾 What number does this code show?
    let score = 5;
    score = score - 1;
    score = score + 5;
    show(score);
29. 29.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
30. 30.💾 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
31. 31.💾 Data saved only on the phone is lost when ___. (a) the screen turns off (b) the app is closed (c) you send a message (d) the phone is lost
32. 32.💾 What number does this code show?
    let stars = 9;
    stars = stars - 7;
    stars = stars + 5;
    show(stars);
33. 33.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
34. 34.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Maths
35. 35.💾 What number does this code show?
    let notes = ["Sports", "Science", "Art", "Hindi"];
    notes.push("Music");
    notes.push("Maths");
    show(notes.length);
36. 36.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
37. 37.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Riya", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Zoya (c) Riya
38. 38.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) your last game level (d) a shared to-do list
39. 39.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Rain", "Sunrise", "Kites", "Ocean"];
    show(songs[0]); (a) Rain (b) Stars (c) Sunrise (d) Kites
40. 40.💾 Saving data in the cloud lets you ___. (a) skip the internet (b) shrink the app (c) never need a password (d) use it on any device

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