[填空题]
A plot of farmland is shown by the shaded region inr oec*)21ofkubog)g29 v . )kx, crlce+mrc(v t0dl(q i uc 808lrdzo4rhe diagram below. The plot has a 4odl(88q0lz di c r0rucurved border which can be described as an arc, PQ, of a circle with centre O and radius,$r=500m$, such that $PÔQ =80^{\circ}$ The straight border of the farmland is defined by the chord PQ.
The farm owner wishes to construct a fence along the curved border of the plot.
1.Find the length of the fence to be built. m
2.Find the area of the farmland, rounding your answer to the nearest $m^2$. $m^2$
