农药存放保管时，应集中在繁育部门，设专人保管，进出仓库应建立登记手续，不准随意存取。
参考答案：对
一根质量分布均匀的米尺（长度为1m），质量为0.2kg，放在水平桌面上，它与桌面间的动摩擦因数为μ=0.16．有14长度露在桌外，现有一水平拉力F=0.4N沿着米尺方向作用于米尺上，作用多长时间，恰好使米尺不从桌边落下．（g取10m/s2）
What is the purpose of the sea horse’s dorsal and pectoral fins().
A. They allow it to maneuver effectively in a small areas.
B. They allow it to swim quickly over long distances.
C. Dorsal and pectoral fins have no function in sea horse.
D. Their multi-colored fins attract shrimp and other food.
