App Dev Worksheet: Variables, Lists and Saving

App development lesson 15: Data: variables, lists and saving · Set 931 · 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.💾 Where should the app save chat messages to friends: on the phone or in the cloud? (a) in the cloud (b) on the phone
2. 2.💾 pop() takes off the last item. What does this code show?
   let notes = ["Science", "Hindi", "Maths", "Art", "Music"];
   notes.pop();
   show(notes[notes.length - 1]); (a) Maths (b) Science (c) Hindi (d) Art
3. 3.💾 Where should the app save photos on two devices: on the phone or in the cloud? (a) on the phone (b) in the cloud
4. 4.True or false: notes to read offline fits saving in the cloud. (a) False (b) True
5. 5.True or false: your last game level fits saving in the cloud. (a) False (b) True
6. 6.Which of these fits saving on the phone? (a) a shared to-do list (b) a class leaderboard (c) a draft you are typing (d) photos on two devices
7. 7.True or false: a class leaderboard fits saving in the cloud. (a) True (b) False
8. 8.💾 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
9. 9.💾 What is a variable? (a) a phone setting (b) a picture (c) a type of screen (d) a named box for a value
10. 10.True or false: notes to read offline fits saving on the phone. (a) True (b) False
11. 11.💾 pop() takes off the last item. What does this code show?
    let friends = ["Kabir", "Zoya", "Aman", "Riya"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Aman (b) Kabir (c) Riya (d) Zoya
12. 12.💾 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
13. 13.💾 What number does this code show?
    let score = 3;
    score = score - 3;
    score = score + 1;
    show(score);
14. 14.Which of these fits saving on the phone? (a) a class leaderboard (b) a shared to-do list (c) the sound on/off setting (d) chat messages to friends
15. 15.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Maths", "Hindi", "Science", "Art"];
    show(notes[1]); (a) Hindi (b) Maths (c) Science (d) Sports
16. 16.Which of these fits saving in the cloud? (a) a draft you are typing (b) notes to read offline (c) a class leaderboard (d) the sound on/off setting
17. 17.💾 What number does this code show?
    let notes = ["Sports", "Maths", "Hindi"];
    notes.push("Art");
    show(notes.length);
18. 18.💾 What number does this code show?
    let points = 3;
    points = points - 2;
    points = points + 1;
    show(points);
19. 19.💾 Where should the app save your last game level: on the phone or in the cloud? (a) in the cloud (b) on the phone
20. 20.💾 pop() takes off the last item. What does this code show?
    let notes = ["Music", "Hindi", "Science"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Science (b) Music (c) Hindi
21. 21.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Music", "Science", "Hindi", "Art"];
    show(notes[1]); (a) Music (b) Sports (c) Science (d) Hindi
22. 22.💾 What does this code show? (Positions start at 0.)
    let notes = ["Sports", "Science", "Art", "Hindi", "Music"];
    show(notes[1]); (a) Art (b) Hindi (c) Science (d) Sports
23. 23.💾 pop() takes off the last item. What does this code show?
    let notes = ["Maths", "Sports", "Science", "Hindi"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Hindi (b) Science (c) Maths (d) Sports
24. 24.💾 What number does this code show?
    let friends = ["Riya", "Aman"];
    friends.push("Arjun");
    friends.push("Kabir");
    show(friends.length);
25. 25.💾 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
26. 26.💾 In most code, the first item of a list is at position ___. (a) 10 (b) 1 (c) 2 (d) 0
27. 27.💾 What number does this code show?
    let coins = 7;
    coins = coins - 1;
    coins = coins + 4;
    show(coins);
28. 28.True or false: photos on two devices fits saving in the cloud. (a) True (b) False
29. 29.💾 What number does this code show?
    let lives = 6;
    lives = lives - 4;
    lives = lives + 2;
    show(lives);
30. 30.Which of these fits saving in the cloud? (a) the sound on/off setting (b) a draft you are typing (c) a shared to-do list (d) notes to read offline
31. 31.💾 pop() takes off the last item. What does this code show?
    let notes = ["Art", "Maths", "Hindi", "Sports"];
    notes.pop();
    show(notes[notes.length - 1]); (a) Sports (b) Art (c) Hindi (d) Maths
32. 32.True or false: a draft you are typing fits saving in the cloud. (a) True (b) False
33. 33.True or false: your last game level fits saving on the phone. (a) False (b) True
34. 34.💾 What does this code show? (Positions start at 0.)
    let friends = ["Arjun", "Meera", "Riya", "Aman"];
    show(friends[2]); (a) Arjun (b) Aman (c) Meera (d) Riya
35. 35.True or false: the sound on/off setting fits saving in the cloud. (a) False (b) True
36. 36.💾 What number does this code show?
    let lives = 3;
    lives = lives - 1;
    lives = lives + 2;
    show(lives);
37. 37.💾 Where should the app save a shared to-do list: on the phone or in the cloud? (a) on the phone (b) in the cloud
38. 38.Which of these fits saving in the cloud? (a) a draft you are typing (b) the sound on/off setting (c) photos on two devices (d) your last game level
39. 39.💾 pop() takes off the last item. What does this code show?
    let friends = ["Zoya", "Kabir", "Arjun"];
    friends.pop();
    show(friends[friends.length - 1]); (a) Arjun (b) Zoya (c) Kabir
40. 40.True or false: a class leaderboard fits saving on the phone. (a) False (b) True

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