A staff assistant at Whitmere Corporation recently determined that the first four units completed in a new manufacturing process took 768 hours to complete, or an average of 192 hours per unit. The assistant also found that when the cumulative output produced doubles, the average labor time declines by 25%. On the basis of this information, how many total hours would Whitmere use if it produces 16 units?

	1,152.
	1,728.
	An amount other than those listed above.
	144.
	108.