砂轮机必须装有用钢板制成、有足够强度的防护罩。防护罩的开口角度不超过(),其中轮轴水平中心线以上不超过65°。
A.90°
B.100°
C.60°
D.120°
参考答案:A
向盛有KI溶液的试管中加入少许CCl4后滴加氯水,CCl4层变 成紫色。如果继续向试管中滴加氯水,振荡,CCl4层会逐渐变浅,最后变成无色。完成下列填空:
(1)写出并配平CCl4层由紫色变成无色的化学反应方程式(如果系数是1,不用填写)
(2)整个过程中的还原剂是__________。
(3)把KI换成KBr,则CCl4层变为__________色:继续滴加氯水,CCl4层的颜色没有变化。Cl2、HIO3、HBrO3氧化性由强到弱的顺序是____________________。
(4)加碘盐中含碘量为20mg~50mg/kg。制取加碘盐(含KIO3的食盐)1000kg,若用KI与Cl2反应制
KIO3,至少需要消耗Cl2__________L(标准状况,保留2位小数)。
Which of the following statements concerning efficient markets and anomalies is the least likely to be correct()
A. Processing information has a cost and takes time, so some market participants may be rewarded for performing fundamental analysis if they act quickly.
B. Strategy risk refers to the fact that the model used to adjust for risk may not be correctly specified.
C. The arbitrage required to exploit an anomaly may not be riskless because there is no guarantee that the price will return to fair value.