分子分母同除以n3，则limn→+∞6n2+23n3+4=limn→+∞6n+2n33 +4n3 =0，
故答案为0．
建筑工地运来水泥74吨，运来的黄沙是水泥的3倍多12吨，运来黄沙多少吨？
—Mom, ________ is my new ruler?
—It’s here, in your bag.
A. What B. Whose C. Where
