跳跃反应的中枢位于
A．脊髓B．延髓C．脑桥D．大脑皮层
参考答案：D
现金等价物是指企业持有的期限短，流动性强，易于转换为已知金额的现金，价值变动风险很小的短期投资。
He didn't tell me _______. [ ]
A. which floor did he live
B. which floor he lives on
C. which floor he lived on
D. which floor he lived
