單項(xiàng)選擇題當(dāng)設(shè)計(jì)無(wú)規(guī)定時(shí),梁或板底模起拱高度宜為全跨長(zhǎng)度的()

A.1/100~3/100
B.1/100~2/100
C.1/1000~3/1000
D.3/1000~5/1000