单选题
1分
The hydraulic oil most likely to thin out when hot and thick when cold would have a viscosity index ...
The hydraulic oil most likely to thin out when hot and thick when cold would have a viscosity index of ______
参考答案: A
参考解析: 当液压油的粘度指数是20的时候,液压油高温变稀,低温变稠,粘温特性较差。