The head nurse is observing a new graduate nurse instill eye drops into a client’s eyes. The head nurse evaluates that the new graduate is using appropriate technique when which of the following steps is incorporated into the procedure

A. The client is instructed to apply pressure to the eyes after instillation of the eye drops.
B. The nurse’s hand is stabilized on the client’s forehead while instilling the drops.
C. The medication is placed onto the client’s sclera.
D. The client is instructed to look at the nurse while the drops are being instille

在粉尘加工厂，为防止粉尘直接进入机械内，应设置机械外罩，外罩的倾角要求保持在()以上。

（A）30° 

（B）40° 

（C）50° 

（D）60°