App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 214 · 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 friends = ["Arjun", "Riya", "Zoya", "Meera"];
   friends.pop();
   show(friends[friends.length - 1]); (a) Riya (b) Arjun (c) Meera (d) Zoya
2. 2.💾 In most code, the first item of a list is at position ___. (a) 2 (b) 10 (c) 1 (d) 0
3. 3.💾 Which works with no internet at all? (a) data saved on the phone (b) a cloud leaderboard (c) a shared chat (d) a cloud backup
4. 4.💾 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
5. 5.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) in the cloud (b) on the phone
6. 6.💾 Which can hold many values in order? (a) a single number (b) a list (c) a button (d) a switch
7. 7.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Ocean", "Stars", "Monsoon"];
   show(songs[0]); (a) Kites (b) Monsoon (c) Ocean (d) Stars
8. 8.💾 What number does this code show?
   let coins = 6;
   coins = coins - 5;
   coins = coins + 2;
   show(coins);
9. 9.Which of these fits saving on the phone? (a) the sound on/off setting (b) chat messages to friends (c) photos on two devices (d) a class leaderboard
10. 10.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
11. 11.💾 What number does this code show?
    let friends = ["Aman", "Meera"];
    friends.push("Riya");
    show(friends.length);
12. 12.💾 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
13. 13.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Science", "Music"];
    notes.push("Art");
    show(notes.length);
14. 14.💾 What number does this code show?
    let friends = ["Zoya", "Riya"];
    friends.push("Arjun");
    show(friends.length);
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 score = 5;
    score = score - 3;
    score = score + 1;
    show(score);
17. 17.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
18. 18.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Science"];
    show(notes[2]); (a) Sports (b) Music (c) Science
19. 19.True or false: photos on two devices fits saving in the cloud. (a) False (b) True
20. 20.💾 What does this code show? (Positions start at 0.)
    let friends = ["Meera", "Aman", "Riya", "Arjun"];
    show(friends[2]); (a) Arjun (b) Meera (c) Aman (d) Riya
21. 21.💾 What number does this code show?
    let stars = 9;
    stars = stars - 3;
    stars = stars + 4;
    show(stars);
22. 22.Which of these fits saving in the cloud? (a) a class leaderboard (b) the sound on/off setting (c) a draft you are typing (d) your last game level
23. 23.Which of these fits saving in the cloud? (a) a draft you are typing (b) chat messages to friends (c) the sound on/off setting (d) notes to read offline
24. 24.Which of these fits saving on the phone? (a) chat messages to friends (b) a shared to-do list (c) a class leaderboard (d) a draft you are typing
25. 25.True or false: a class leaderboard fits saving in the cloud. (a) False (b) True
26. 26.💾 What number does this code show?
    let notes = ["Maths", "Sports", "Hindi"];
    notes.push("Art");
    notes.push("Science");
    show(notes.length);
27. 27.💾 What number does this code show?
    let points = 7;
    points = points - 1;
    points = points + 3;
    show(points);
28. 28.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Hindi", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Science (d) Sports
29. 29.💾 What is a variable? (a) a picture (b) a type of screen (c) a named box for a value (d) a phone setting
30. 30.True or false: a draft you are typing fits saving on the phone. (a) False (b) True
31. 31.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
32. 32.💾 What number does this code show?
    let stars = 4;
    stars = stars - 2;
    stars = stars + 4;
    show(stars);
33. 33.Which of these fits saving in the cloud? (a) the sound on/off setting (b) your last game level (c) a shared to-do list (d) notes to read offline
34. 34.True or false: a draft you are typing fits saving in the cloud. (a) False (b) True
35. 35.💾 What number does this code show?
    let friends = ["Arjun", "Zoya"];
    friends.push("Meera");
    friends.push("Aman");
    show(friends.length);
36. 36.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) the sound on/off setting (d) photos on two devices
37. 37.💾 pop() takes off the last item. What does this code show?
    let notes = ["Sports", "Maths", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Maths (b) Sports (c) Science
38. 38.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
39. 39.Which of these fits saving on the phone? (a) a class leaderboard (b) chat messages to friends (c) photos on two devices (d) your last game level
40. 40.💾 pop() takes off the last item. What does this code show?
    let friends = ["Riya", "Zoya", "Aman", "Kabir", "Meera"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Zoya (c) Kabir (d) Riya

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