爆炸品主要具有反应速度极快，放出大量的热，产生大量的气体等特性。
参考答案：对
下列接受名片时唯一正确的做法是（）
A.接受名片时要用双手
B.大声念出名片上的头衔
C.接过名片马上放人兜内
D.传递名片将正面朝向自己
The price of product Z decreased from $ 2.50 per unit to 2.00 per unit. Since the price decreased, demand has gone up from 3 million units to 4 million units. Calculate the price elasticity of demand and determine if the demand is elastic or inelastic.Price elasticity of demand Elasticity（）
A. -1.29 elastic
B. -2.00 inelastic
C. -1.29 inelastic
