在一张长16厘米，宽12厘米的长方形纸板上画一个最大的圆，则这个圆的半径是（ ）。
6厘米
根据物质分类知识判断，下列物质属于纯净物的是（ ）
A．汽水
B．矿泉水
C．自来水
D．冰水混合物
A psychotic client reports to the evening nurse that the day nurse put something suspicious in his water with his medication. The nurse replies, "You’re worried about your medication" The nurse’s communication is（）
A. an example of presenting reality.
B. reinforcing the client’s delusions.
C. focusing on emotional content.
D. a nontherapeutic technique called mind reading.
