单击此处编辑母版标题样式单击此处编辑母版文本样式第二级第三级第四级第五级混合运算大汽车和小汽车一共有多少辆小汽车比大汽车多多少辆我们停了8辆大汽车50元我们停了8辆大汽车50元付50元停8辆大汽车还剩多少元算一算：3×620 9×8-32405×7 42-4×9=38=75=40=6

参考答案Number of cars: 25 millionIncrease in last ten years: 30Amount of TV advertising: 14Short car journeys: 25 under 2 milesChemicals produced by cars: carbon monoxideHealth effects of air pollution: