* Returns a hexadecimal representation of the unsigned binary number. Uses

* an underscore to separate each group of 4 characters.

*

* @param b The binary number

* @return The hexadecimal representation of the binary number.

*/

public static String toHexString(boolean[] b) {

// PROGRAM 1: Student must complete this method

// return value is a placeholder, student should replace with correct return

return "not completed";

}