[填空题]
A race car driver muico9urby/9 .7nv n6dt+ wa j*bvx+1g tstp/m e(ah0h t7+mu4p;z9od c ni average $200 \; km/h$ over the course of a time trial lasting ten laps. If the first nine laps were done at $198 \; km/h$, what average speed must be maintained for the last lap? $km/h$
