为了保证化工厂用火安全,动火现场的厂房内和容器内可燃物应保证在百分之()以下。 ["A、0.1,0.2","B、0.2,0.01","C、0.2,0.1","D、0.1,0.02"]
调节阀按其使用的能源形式可分为()。 ["A、压力调节阀","B、电动调节阀","C、液动调节阀","D、气动调节阀"]
调节阀按阀芯动作形式可分为()等类型。 ["A、气开阀","B、气关阀","C、直行程式","D、角行程式"]
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