Add my answer to Exercise 1.5.

Included is the following file:

	Exercise_1.5.pdf
	Exercise_1.5.tm

Thank you!
							Lawrence X. Amlord
							  Oct 19th, 2013
							  Xi'an, China
Add my proof to Exercise X1.3.

Included are the following 2 files:

	Exercise_X1.3.pdf
	Exercise_X1.3.tm

Thank you!
							Lawrence X. Amlord
							  Oct 19th, 2013
							  Xi'an, China