蛇靠什么来发现别的生物的?()
A.生物的热源
B.生物的运动
C.生物发出的声音
D.生物的气味
参考答案:A
Senior citizens in that country enjoy certain_______, such as free medical care and free entry to public parks ?
A.privileges
B.reputations
C.invitations
D.possessions
国家环保规定粉尘外排浓度≯100mg/m3。