## CS 1401, Quiz #4

Date: Monday, September 26, 2005
Name (please type legibly, ideally in block letters): ______________________________________________________________________

1. Write down a method that computes the tangent tan(x) as the ratio of sin(x) and cos(x). This method should have the following header:

```public static double tangent(double x){

```
2. To attract more students, UTEP decided to officially change the name to The Great University. Because of this change, we must change the official letters. Describe the code that, given a string letter in which the word "UTEP" appears exactly once, replaces the word "UTEP" in this string with the sequence "The Great University". For example, the string
```UTEP won the football game.
```
should be replaced with a string
```The Great University won the football game.
```
Hints:
• first, find the location of the word "UTEP" in the the string letter (by using the string method indexOf);
• then, combine the following three strings:
• the substring before the word "UTEP",
• the substring "The Great University", and
• the substring after the word "UTEP".
The length of a string s can be found as s.length(); a substring can be found as s.substring(first_in,first_out).
```

```
3. What is a Boolean variable? What values can it take? Why do we need Boolean variables?