Add my answer to Exercise 3.30.

Included are the following 3 files:

	Exercise_3.30.pdf
	Exercise_3.30.scm
	Exercise_3.30.tm

Thank you!
							Lawrence X. Amlord
							  Oct 10th, 2013
							  Xi'an, China
Update my answer to Exercise 3.29.

I've correct an error in computing the or-gate-delay.

Modified are the following 2 files:

	Exercise_3.29.pdf
	Exercise_3.29.tm

Than you!
							Lawrence X. Amlord
							  Oct 10th, 2013
							  Xi'an, China