App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 901 · 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) chat messages to friends (b) notes to read offline (c) a shared to-do list (d) a class leaderboard
2. 2.💾 Which can hold many values in order? (a) a switch (b) a button (c) a single number (d) a list
3. 3.💾 What number does this code show?
   let friends = ["Zoya", "Riya", "Kabir", "Arjun"];
   friends.push("Aman");
   show(friends.length);
4. 4.True or false: a shared to-do list fits saving on the phone. (a) True (b) False
5. 5.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
6. 6.Which of these fits saving on the phone? (a) photos on two devices (b) chat messages to friends (c) a draft you are typing (d) a shared to-do list
7. 7.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
8. 8.💾 What number does this code show?
   let score = 4;
   score = score - 2;
   score = score + 1;
   show(score);
9. 9.💾 What number does this code show?
   let notes = ["Music", "Sports"];
   notes.push("Art");
   show(notes.length);
10. 10.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) on the phone (b) in the cloud
11. 11.Which of these fits saving on the phone? (a) a class leaderboard (b) your last game level (c) chat messages to friends (d) photos on two devices
12. 12.💾 What number does this code show?
    let stars = 5;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
13. 13.True or false: a shared to-do list fits saving in the cloud. (a) False (b) True
14. 14.💾 What is a variable? (a) a phone setting (b) a named box for a value (c) a picture (d) a type of screen
15. 15.💾 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
16. 16.💾 What number does this code show?
    let friends = ["Riya", "Zoya", "Aman"];
    friends.push("Arjun");
    show(friends.length);
17. 17.Which of these fits saving on the phone? (a) a shared to-do list (b) the sound on/off setting (c) photos on two devices (d) a class leaderboard
18. 18.💾 Which works with no internet at all? (a) a cloud leaderboard (b) a shared chat (c) a cloud backup (d) data saved on the phone
19. 19.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 0 (d) 2
20. 20.💾 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
21. 21.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) photos on two devices (d) notes to read offline
22. 22.💾 What does this code show? (Positions start at 0.)
    let friends = ["Riya", "Arjun", "Aman"];
    show(friends[0]); (a) Riya (b) Arjun (c) Aman
23. 23.💾 pop() takes off the last item. What does this code show?
    let notes = ["Hindi", "Maths", "Art"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Maths
24. 24.Which of these fits saving in the cloud? (a) chat messages to friends (b) the sound on/off setting (c) a draft you are typing (d) your last game level
25. 25.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
26. 26.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
27. 27.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
28. 28.💾 What number does this code show?
    let stars = 8;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
29. 29.💾 What does this code show? (Positions start at 0.)
    let songs = ["Kites", "Rain", "Ocean", "Sunrise", "Stars"];
    show(songs[3]); (a) Kites (b) Ocean (c) Rain (d) Sunrise
30. 30.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Hindi", "Maths", "Science", "Music"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Hindi (c) Maths (d) Science
31. 31.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) the sound on/off setting (d) a shared to-do list
32. 32.💾 What number does this code show?
    let friends = ["Riya", "Zoya"];
    friends.push("Meera");
    friends.push("Aman");
    show(friends.length);
33. 33.True or false: a class leaderboard fits saving on the phone. (a) True (b) False
34. 34.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Art", "Maths", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Music (b) Art (c) Maths (d) Sports
35. 35.💾 pop() takes off the last item. What does this code show?
    let songs = ["Ocean", "Stars", "Monsoon"];
    songs.pop();
    show(songs[songs.length - 1]); (a) Stars (b) Ocean (c) Monsoon
36. 36.💾 What number does this code show?
    let notes = ["Science", "Maths"];
    notes.push("Hindi");
    show(notes.length);
37. 37.💾 What number does this code show?
    let songs = ["Ocean", "Rain", "Stars"];
    songs.push("Kites");
    show(songs.length);
38. 38.💾 What number does this code show?
    let songs = ["Sunrise", "Kites"];
    songs.push("Stars");
    show(songs.length);
39. 39.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 5;
    show(stars);
40. 40.True or false: your last game level fits saving in the cloud. (a) False (b) True

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