Update my answer to Exercise 2.26.

Modified is the following 2 files:

	Exercise_2.26.pdf
	Exercise_2.26.tm

Besides, I've renamed the Scheme source file:

	Exercise_2.26.scm --> Test_for_Exercise_2.26.scm

Thank you!
							Lawrence X. Amlord
							  Nov 12th, 2013
							  Xi'an, China