App Dev Worksheet: Functions

App development lesson 20: Functions · Set 825 · 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.

NameDateTime takenScore ___ / 40

1.🧰 How do you run (call) a function called greet? (a) #greet (b) greet[] (c) greet() (d) run greet
2.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Arjun")); (a) Welcome, Arjun! (b) Welcome, name! (c) Arjun (d) greet
3.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(30, 6));
4.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Aman")); (a) greet (b) Aman (c) Hello, name! (d) Hello, Aman!
5.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(20, 2));
6.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(6));
7.🧰 A museum app works out the entry fee. What number does this code show?
function fee(age) {
  if (age < 5) {
    return 0;
  }
  return 20;
}
show(fee(5) + fee(10));
8.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(5));
9.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(3));
10.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(1));
11.🧰 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(10) + fee(12));
12.🧰 What is a function? (a) a type of phone (b) a screen size (c) a list of colours (d) a named block of code
13.🧰 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(9) + fee(9));
14.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Riya")); (a) Welcome, name! (b) Welcome, Riya! (c) greet (d) Riya
15.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(27));
16.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(95, 3));
17.🧰 A museum app works out the entry fee. What number does this code show?
function fee(age) {
  if (age < 5) {
    return 0;
  }
  return 40;
}
show(fee(10) + fee(1));
18.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(16));
19.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(23));
20.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(2));
21.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Riya")); (a) Hello, name! (b) Riya (c) greet (d) Hello, Riya!
22.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(15));
23.🧰 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(1) + fee(10));
24.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(10));
25.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Zoya")); (a) Zoya (b) greet (c) Hello, name! (d) Hello, Zoya!
26.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Meera")); (a) greet (b) Meera (c) Welcome, name! (d) Welcome, Meera!
27.🧰 A museum app works out the entry fee. What number does this code show?
function fee(age) {
  if (age < 5) {
    return 0;
  }
  return 60;
}
show(fee(2) + fee(5));
28.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(3));
29.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Arjun")); (a) Well done, name! (b) Arjun (c) greet (d) Well done, Arjun!
30.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(39));
31.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(5));
32.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(35));
33.🧰 Why write a function? (a) to slow the app (b) to reuse code (c) to hide errors (d) to make code longer
34.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(100, 5));
35.🧰 What does return do in a function? (a) closes the screen (b) sends back a value (c) deletes the app (d) repeats the code
36.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(1));
37.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(35));
38.🧰 A museum app works out the entry fee. What number does this code show?
function fee(age) {
  if (age < 5) {
    return 0;
  }
  return 40;
}
show(fee(8) + fee(8));
39.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Meera")); (a) greet (b) Well done, name! (c) Well done, Meera! (d) Meera
40.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(1));

Answer key

greet()
Welcome, Arjun!
180
Hello, Aman!
40
18
40
100
70
40
100
a named block of code
60
Welcome, Riya!
81
285
40
48
46
70
Hello, Riya!
45
30
30
Hello, Zoya!
Welcome, Meera!
60
60
Well done, Arjun!
117
80
105
to reuse code
500
sends back a value
60
70
80
Well done, Meera!
50

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