苹果每千克a元，超过5千克的部分按8折优惠，小晶购苹果9千克，应付（ ）元．
8.2a
______是智慧的最高表现，因而从逻辑学中引进______的概念作为划分智慧阶段的依据。
—Why weren’t you at the meeting?
—I for a call from my husband in Guangdong.
A．waited
B．had waited
C．was waiting
D．will wait
