How long did you _____ eating in the restaurant? [ ]
A. spend
B. cost
C. take
D. pay
答案:A
农业气象灾害风险区划要求空间分辨率不低于()。
A.100m×100m
B.250m×250m
C.500m×500m
在四元被动红外探测器的防护区内如有老鼠活动可以引起系统报警