题目

 The Yangtze River is almost ______ the Pearl River.     A. two times as longer        B. twice longer than      C. twice as longer as          D. two time the length of 答案：B计算下列各题，要写出主要计算过程，能用简便方法的要用简便方法计算．①2013-44-156           ②2.3×1.2+4.5÷0.75            ③4.9+4.9×19④3÷12-14×310    ⑤415×[（34-712）÷49]⑥813÷7+17×513．