[填空题]
A 65-kg person jumps from a window tt ;f-t ordo94d,a/jmso a fire net 18 m below, which stretches tr 9,q f8 ,xxmfg-n 7z57jawjwwhe net 1.1 m. Assume that the net behaves like af wz jm7g,7aq85-xwf9 x wrnj, simple spring, and
(a) calculate how much it would stretch if the same person were lying in it. m
(b) How much would it stretch if the person jumped from 35 m? m