Add my answer to Exercise 3.70.

Included are the following 2 files:

	Exercise_3.70.scm
	Test_for_Exercise_3.70.scm

Thank you!
							Lawrence X. Amlord
							  Dec 4th, 2013
							  Xi'an, China
Add my answer to Exercise 3.71.

Included is the following file:

	Exercise_3.71.scm

Thank you!
							Lawrence X. Amlord
							  Dec 5th, 2013
							  Xi'an, China
Add my answer to Exercise 3.72.

Included is the following file:

	Exercise_3.72.scm

Thank you!
							Lawrence X. Amlord
							  Dec 5th, 2013
							  Xi'an, China