리습 길이합 단위 수정

선길이 합 구하는 리습인데 단위를 mm→m로 변경하고 소수점 두자리로 하고 싶습니다.
부탁 드리겠습니다. 감사합니다.

(defun c:lle (/ ent n dis ent_l #a #ad #as )
(setvar "cmdecho" 0)
(setq ent (ssget '((0 . "LINE,CIRCLE,ARC,POLYLINE,LWPOLYLINE,ELLIPSE,SPLINE"))))
(setq n 0 dis 0)
(repeat (sslength ent)
(setq ent_l (ssname ent n))
(command "lengthen" ent_l "")
(setq dis (+ dis (GETVAR "PERIMETER")))
(setq n (1+ n))
)
(setq #a(strcat " L = " (rtos dis)))
(prompt (strcat "n" #a))
(vl-load-com)
(setq #ad(vla-get-activedocument(vlax-get-acad-object)))
(setq #as
(if (> (vla-get-activespace #ad) 0)
(vla-get-modelspace #ad)
(vla-get-paperspace #ad)
);;if
);;setq
(vla-addtext #as #a (vlax-3d-point(getpoint "n≫≫≫Pick text point:"))(* (getvar "textsize")2.5))
(mapcar 'vlax-release-object (list #as #ad))
(princ)
(setvar "cmdecho" 1)
)