App Dev Worksheet: Functions

App development lesson 20: Functions · Set 196 · 40 questions

Developer's tip (Write once, use often): function name(parameter) { …; return result; } — call it with name(value). Work out each call separately, then finish the line. Inside a function, if / return can give different results for different inputs.

1. 1.🧰 What number does this code show?
   function total(price, qty) {
     return price * qty;
   }
   show(total(10, 2));
2. 2.🧰 What does this code show?
   function greet(name) {
     return "Hello, " + name + "!";
   }
   show(greet("Arjun")); (a) greet (b) Hello, name! (c) Arjun (d) Hello, Arjun!
3. 3.🧰 What number does this code show?
   function points(stars) {
     return stars * 10 + 5;
   }
   show(points(1) + points(2));
4. 4.🧰 What number does this code show?
   function total(price, qty) {
     return price * qty;
   }
   show(total(100, 5));
5. 5.🧰 What number does this code show?
   function total(price, qty) {
     return price * qty;
   }
   show(total(75, 3));
6. 6.🧰 What number does this code show?
   function double(n) {
     return n * 2;
   }
   show(double(29));
7. 7.🧰 What number does this code show?
   function points(stars) {
     return stars * 10 + 5;
   }
   show(points(5) + points(2));
8. 8.🧰 What number does this code show?
   function total(price, qty) {
     return price * qty;
   }
   show(total(25, 2));
9. 9.🧰 What number does this code show?
   function total(price, qty) {
     return price * qty;
   }
   show(total(50, 5));
10. 10.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(15));
11. 11.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Aman")); (a) greet (b) Well done, Aman! (c) Aman (d) Well done, name!
12. 12.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Kabir")); (a) Welcome, Kabir! (b) Kabir (c) Welcome, name! (d) greet
13. 13.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(4));
14. 14.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(70, 4));
15. 15.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(12));
16. 16.🧰 Why write a function? (a) to make code longer (b) to slow the app (c) to reuse code (d) to hide errors
17. 17.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(34));
18. 18.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Riya")); (a) Well done, Riya! (b) Riya (c) Well done, name! (d) greet
19. 19.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Zoya")); (a) Welcome, name! (b) greet (c) Zoya (d) Welcome, Zoya!
20. 20.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(27));
21. 21.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(20));
22. 22.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(4));
23. 23.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(35, 6));
24. 24.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Riya")); (a) Hi, name! (b) greet (c) Riya (d) Hi, Riya!
25. 25.🧰 In function tip(bill), what is bill? (a) a parameter (b) a screen (c) an event (d) a loop
26. 26.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Kabir")); (a) Kabir (b) Well done, Kabir! (c) Well done, name! (d) greet
27. 27.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 50;
    }
    show(fee(11) + fee(5));
28. 28.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(6));
29. 29.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(28));
30. 30.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(25, 5));
31. 31.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(22));
32. 32.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 50;
    }
    show(fee(4) + fee(1));
33. 33.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(65, 3));
34. 34.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Meera")); (a) Hi, Meera! (b) Meera (c) Hi, name! (d) greet
35. 35.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 30;
    }
    show(fee(2) + fee(3));
36. 36.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(14));
37. 37.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(19));
38. 38.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(30, 3));
39. 39.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 50;
    }
    show(fee(11) + fee(1));
40. 40.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 30;
    }
    show(fee(4) + fee(11));

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