The 3rd one
but he should also jot down a list of questions he intends to ask during each call and should be writing down the responses he receives as well as any follow up numbers etc that he needs to call <span />
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.