Update my answer to Exercise 2.47.

Updated are the following 2 files:

	Exercise_2.47.pdf
	Exercise_2.47.tm

Thank you!
							Lawrence R. Amlord
							   Jun 15th, 2013
							   Xi'an, China
Add my answer to Exercise 2.49.

Included is the following file:

	Exercise_2.49.scm

Thank you!
							Lawrence R. Amlord
							   Jul 16th, 2013
							   Xian, China