Add my answer to Exercise 3.39.

Included are the following 2 files:

	Exercise_3.39.pdf
	Exercise_3.39.tm

Thank you!
							Lawrence X. Amlord
							  Nov 1st, 2013
							  Xi'an, China
Add my answer to Exercise 3.40.

Included are the following 2 files:

	Exercise_3.40.pdf
	Exercise_3.40.tm

Thank you!
							Lawrence X. Amlord
							  Nov 1st, 2013
							  Xi'an, China
Add my answer to Exercise 3.41.

Included are the following 2 files:

	Exercise_3.41.pdf
	Exercise_3.41.tm

Thank you!
							Lawrence X. Amlord
							  Nov 2nd, 2013
							  Xi'an, China
Add my answer to Exercise 3.42.

Included are the following 2 files:

	Exercise_3.42.pdf
	Exercise_3.42.tm

Thank you!
							Lawrence X. Amlord
							  Nov 2nd, 2013
							  Xi'an, China
Add my answer to Exercise 3.43.

Included are the following 2 files:

	Exercise_3.43.pdf
	Exercise_3.43.tm

Thank you!
							Lawrence X. Amlord
							  Nov 3rd, 2013
							  Xi'an, China