如圖所示,正五邊形的內(nèi)切圓半徑R=()
A.64.348B.61.937C.72.812D.45
如圖所示,小圓半徑為15,則大圓半徑為()
A.47.883B.48.742C.48.541D.48.151
如圖所示,多段線的總長(zhǎng)度是多少()
A.130.527B.192.306C.179.171D.179.205