Number one is D and number two is B
Science must be used to figure out the correct weight, length, and what material it is made out of to be the most successful at its job. Technology must be used to make sure that the calculations are correct and to use a 3d printer or something like that to make it, that or robots/tools.
There are many physical advantages of administering a dual spinal epidural or walking epidural during childbirth like walking epidural uses smaller needles and a system for administering an anesthetic, it also permits the woman to move freely during labor, and it has fewer effects than a traditional epidural. The disadvantage is a walking epidural cost less to administer.
Some of the reasons for using a zone defense are: The opposing team has a player/players too quick (in the case of guards) or too big (in the case of forwards or centers) for a man-to-man defense to be effective. Many zones pack defenders in the lane but allow the offensive team to take long-range shots
