Add my answer to Exercise_2.42.

Included are the following 4 files:

	Exercise_2.42.pdf
	Exercise_2.42.scm
	Exercise_2.42.tm
	Test_for_Exercise_2.42.scm

Thank you!
							Lawrence R. Amlord
							   Jun 7th, 2013
							   Xi'an, China
Add my answer to Exercise 2.43.

Included are the following 2 files:

	Exercise_2.43.pdf
	Exercise_2.43.tm

Thank you!
							Lawrence R. Amlord
							   Jun 7th, 2013
							   Xi'an, China