Koj cov kev xav tau, peb qhov kev paub
Kev tswj cov khoom siv: ntau txoj kev xaiv cov khoom siv tseem ceeb (ib nrab tseem ceeb, ntoo pulp, tag nrho cov tseem ceeb).




Cov ntawv qhia zis, cov txheej tshem ntxhiab, thiab lwm yam.
Kev kho qhov tseeb ntawm qhov loj / elasticity / tuab (± 0.5 hli qhov tseeb).
5-10 hnub rau kev tsim qauv.
Cov lus qhia yooj ywm.