[填空题]
What is the linear s5 +sgt81/x 7e nugp4j-tfhulspef :ew6 l.gv8zfov:rx :ni(xx.ed of a point (a) on the equator, $m/s$ (b) on the Arctic Circle (latitude 66.5$^{\circ} $ N), $m/s$ (c) at a latitude of 45.0$^{\circ} $ N, due to the Earth’s rotation? $m/s$