[填空题]
John is building furniture using cylindrical logs of length 1.8 m and radius b txvk /ui:h.n5+3mza 9.*rmm2 rpx.cqd (5jbag 32i2zi2 cm. A wedge ijbp*5m2giad.xmc q23z ri2( rs 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. $cm^3$
