App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 577 · 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.💾 What number does this code show?
   let friends = ["Meera", "Aman", "Arjun", "Kabir"];
   friends.push("Riya");
   show(friends.length);
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.True or false: your last game level fits saving in the cloud. (a) True (b) False
4. 4.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
5. 5.💾 What number does this code show?
   let stars = 6;
   stars = stars - 4;
   stars = stars + 4;
   show(stars);
6. 6.💾 pop() takes off the last item. What does this code show?
   let notes = ["Art", "Sports", "Hindi", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Art (b) Music (c) Hindi (d) Sports
7. 7.💾 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
8. 8.Which of these fits saving in the cloud? (a) your last game level (b) notes to read offline (c) a draft you are typing (d) a class leaderboard
9. 9.💾 What number does this code show?
   let songs = ["Ocean", "Sunrise"];
   songs.push("Rain");
   show(songs.length);
10. 10.💾 What does this code show? (Positions start at 0.)
    let songs = ["Rain", "Sunrise", "Stars", "Kites", "Ocean"];
    show(songs[4]); (a) Stars (b) Ocean (c) Sunrise (d) Rain
11. 11.💾 What number does this code show?
    let score = 8;
    score = score - 1;
    score = score + 3;
    show(score);
12. 12.💾 Which can hold many values in order? (a) a switch (b) a list (c) a button (d) a single number
13. 13.Which of these fits saving on the phone? (a) chat messages to friends (b) a class leaderboard (c) the sound on/off setting (d) photos on two devices
14. 14.Which of these fits saving on the phone? (a) a draft you are typing (b) chat messages to friends (c) a class leaderboard (d) photos on two devices
15. 15.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
16. 16.💾 What number does this code show?
    let points = 6;
    points = points - 3;
    points = points + 5;
    show(points);
17. 17.💾 What number does this code show?
    let notes = ["Art", "Hindi", "Sports"];
    notes.push("Maths");
    show(notes.length);
18. 18.💾 Saving data in the cloud lets you ___. (a) never need a password (b) use it on any device (c) shrink the app (d) skip the internet
19. 19.💾 What does this code show? (Positions start at 0.)
    let songs = ["Sunrise", "Rain", "Ocean"];
    show(songs[2]); (a) Sunrise (b) Ocean (c) Rain
20. 20.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Art", "Hindi", "Sports"];
    show(notes[2]); (a) Art (b) Sports (c) Maths (d) Hindi
21. 21.💾 What is a variable? (a) a picture (b) a phone setting (c) a named box for a value (d) a type of screen
22. 22.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Zoya", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Meera (c) Zoya
23. 23.True or false: chat messages to friends fits saving on the phone. (a) False (b) True
24. 24.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
25. 25.💾 What number does this code show?
    let stars = 3;
    stars = stars - 2;
    stars = stars + 1;
    show(stars);
26. 26.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
27. 27.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Kabir", "Zoya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Zoya (c) Kabir
28. 28.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
29. 29.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
30. 30.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Stars", "Ocean", "Rain"];
    show(songs[0]); (a) Rain (b) Monsoon (c) Ocean (d) Stars
31. 31.Which of these fits saving in the cloud? (a) notes to read offline (b) a draft you are typing (c) your last game level (d) photos on two devices
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Monsoon", "Stars", "Rain", "Ocean"];
    show(songs[0]); (a) Ocean (b) Stars (c) Monsoon (d) Rain
33. 33.💾 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
34. 34.💾 What number does this code show?
    let points = 6;
    points = points - 6;
    points = points + 4;
    show(points);
35. 35.💾 Which works with no internet at all? (a) a cloud backup (b) a cloud leaderboard (c) a shared chat (d) data saved on the phone
36. 36.💾 pop() takes off the last item. What does this code show?
    let friends = ["Arjun", "Kabir", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Kabir (b) Meera (c) Arjun
37. 37.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
38. 38.💾 What number does this code show?
    let score = 8;
    score = score - 3;
    score = score + 5;
    show(score);
39. 39.💾 What number does this code show?
    let notes = ["Art", "Maths", "Sports"];
    notes.push("Hindi");
    show(notes.length);
40. 40.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone

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