火炬系统的常明火点火前要确保（）有水封。 ["水封罐","火炬分液罐","缓冲制度","阻火器"]
等位基因的胡作不包括（） ["共显性","镶嵌显性","不完全显性","上位作用"]
On all vessels equipped with refrigeration units of over 20 cubic foot capacity, （）. ["a gas mask suitable for protection against each refrigerant used, or a self contained breathing apparatus must be provided","it is the sole responsibility of the chief engineer to ascertain that all members of the engineering department are familiar with the use of gas masks or breathing apparatus","spare charges shall be carried for at least 50% of each size and variety of gas masks and\/or self contained breathing apparatus","all of the above"]
企业、事业单位以及其他组织开业或者成立6个月尚未组建工会，职工有建会意愿的，上级工会（）派员帮助和指导职工组建工会。 ["应当","可以","根据情况","必须"]
（）适合于中小银行以及实力较弱的银行。 ["市场渗透","混合型","逆向型战略","紧张战略"]
简述会展项目评估的基本含义。
