[填空题]
John is building furniture using cylindy;m6bp,7 hh9+qxng+- nxz l qoricalu +oy0ur erdy bw+6.v7 logs of length 1.81.8 m and radius 9.29.2 cm.dw 07u .rvuy++rbeo6y A wedge is cut from one log and the cross-section of this log is illustrated in the following diagram.
1.Find the length of the wedge arc, ABC. cm
2.Find the area of the empty sector, OABC. $cm^2$
3.Find the volume of each log. $cm^3$