his average speed had been 299 miles per hour

his average speed had been 299 miles per hour His average speed had been 301 miles per hour.句子成分 求：the average speed over the 8 miles is 33 miles per hour.怎么 一道英文数学题,求解Becca runs at an average speed of 4 miles per hour his average speed had been 301 这里面的been是什么 Was his average speed incorrectly declared to be 299 miles p the train is moving at the speed of 120 miles per hour. Although Campbell reached a speed of over 304 miles per hour 英语翻译1、The speed limit is fifty-five miles per hour.How far w 英语翻译reach a speed of over 50 miles per hour,这里的a speed of是固定 You must have been driving at seventy miles an/per hour. A man drives from his home at 30 miles per hour to the shopp