[填空题]
What is the linear speed o d+g/a37kc mpo fm ul*+h((9p;(() mgyedbp wjt16xsxtdlwg)f 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? $m/s$