App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 606 · 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.True or false: notes to read offline fits saving in the cloud. (a) True (b) False
2. 2.True or false: your last game level fits saving in the cloud. (a) False (b) True
3. 3.💾 What does this code show? (Positions start at 0.)
   let friends = ["Arjun", "Kabir", "Riya"];
   show(friends[1]); (a) Arjun (b) Riya (c) Kabir
4. 4.💾 Where should the app save your last game level: on the phone or in the cloud? (a) on the phone (b) in the cloud
5. 5.💾 What number does this code show?
   let points = 4;
   points = points - 2;
   points = points + 4;
   show(points);
6. 6.💾 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
7. 7.💾 What number does this code show?
   let notes = ["Science", "Music"];
   notes.push("Maths");
   notes.push("Sports");
   show(notes.length);
8. 8.💾 What does this code show? (Positions start at 0.)
   let songs = ["Kites", "Sunrise", "Monsoon", "Ocean", "Rain"];
   show(songs[3]); (a) Kites (b) Monsoon (c) Sunrise (d) Ocean
9. 9.Which of these fits saving in the cloud? (a) your last game level (b) a draft you are typing (c) chat messages to friends (d) the sound on/off setting
10. 10.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 2;
    show(score);
11. 11.True or false: the sound on/off setting fits saving in the cloud. (a) True (b) False
12. 12.True or false: a shared to-do list fits saving on the phone. (a) False (b) True
13. 13.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Kites", "Ocean", "Rain"];
    show(songs[0]); (a) Stars (b) Rain (c) Kites (d) Ocean
14. 14.💾 What is a variable? (a) a picture (b) a type of screen (c) a named box for a value (d) a phone setting
15. 15.💾 What number does this code show?
    let lives = 5;
    lives = lives - 3;
    lives = lives + 5;
    show(lives);
16. 16.💾 pop() takes off the last item. What does this code show?
    let friends = ["Aman", "Riya", "Meera", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Riya (b) Arjun (c) Meera (d) Aman
17. 17.💾 What does this code show? (Positions start at 0.)
    let notes = ["Maths", "Hindi", "Art", "Music", "Sports"];
    show(notes[2]); (a) Music (b) Art (c) Maths (d) Hindi
18. 18.💾 Saving data in the cloud lets you ___. (a) shrink the app (b) skip the internet (c) never need a password (d) use it on any device
19. 19.Which of these fits saving in the cloud? (a) a class leaderboard (b) your last game level (c) a draft you are typing (d) the sound on/off setting
20. 20.💾 Where should the app save a class leaderboard: on the phone or in the cloud? (a) in the cloud (b) on the phone
21. 21.Which of these fits saving on the phone? (a) your last game level (b) a class leaderboard (c) chat messages to friends (d) a shared to-do list
22. 22.💾 What does this code show? (Positions start at 0.)
    let notes = ["Hindi", "Science", "Music", "Maths", "Sports"];
    show(notes[0]); (a) Science (b) Music (c) Hindi (d) Maths
23. 23.💾 Which can hold many values in order? (a) a single number (b) a switch (c) a list (d) a button
24. 24.Which of these fits saving on the phone? (a) photos on two devices (b) the sound on/off setting (c) a class leaderboard (d) a shared to-do list
25. 25.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Riya", "Aman"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Riya
26. 26.💾 Data saved only on the phone is lost when ___. (a) you send a message (b) the screen turns off (c) the app is closed (d) the phone is lost
27. 27.True or false: chat messages to friends fits saving in the cloud. (a) False (b) True
28. 28.💾 What number does this code show?
    let friends = ["Riya", "Aman", "Arjun", "Meera"];
    friends.push("Kabir");
    show(friends.length);
29. 29.💾 What number does this code show?
    let friends = ["Meera", "Aman"];
    friends.push("Riya");
    show(friends.length);
30. 30.💾 What number does this code show?
    let notes = ["Sports", "Hindi", "Art"];
    notes.push("Music");
    show(notes.length);
31. 31.Which of these fits saving in the cloud? (a) a draft you are typing (b) photos on two devices (c) the sound on/off setting (d) your last game level
32. 32.💾 What does this code show? (Positions start at 0.)
    let songs = ["Stars", "Kites", "Monsoon"];
    show(songs[0]); (a) Monsoon (b) Kites (c) Stars
33. 33.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Science", "Maths", "Hindi", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Maths (c) Science (d) Art
34. 34.💾 Where should the app save notes to read offline: on the phone or in the cloud? (a) in the cloud (b) on the phone
35. 35.💾 pop() takes off the last item. What does this code show?
    let notes = ["Science", "Music", "Sports", "Art", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Art (b) Music (c) Sports (d) Science
36. 36.💾 What number does this code show?
    let points = 5;
    points = points - 5;
    points = points + 3;
    show(points);
37. 37.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
38. 38.Which of these fits saving on the phone? (a) a draft you are typing (b) a shared to-do list (c) photos on two devices (d) chat messages to friends
39. 39.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 1;
    show(lives);
40. 40.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 2 (d) 0

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