[填空题]
What is the linear sp n0;ek)2z3penfpavy,e23fnor6re *up. z br+ eed of a poi;ngq p 3usx 2h(p*wnlww (9c;bnt (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? $m/s$