2008-09-29, 01:05 AM
JoeTang Wrote:Tell me what Pn and P0 are supposed to be, because I don't see a use for momentum in this question.
P0, Pn, are points, p0 is the starting point, pn is the ending point, i don't think it has much significance, because every question, pn and p0 is at the same vertical level o.O.

