An advantage of a dry chemical over a carbon dioxide fire extinguish is its（）. ["greater range","effective on all types of fires","cleanliness","All of the above"]
文献法具有比较突出的特点是（）。 ["时空性","间接性","效率高","花费少"]
按照不同的职能非营利组织可分为哪些？
An advantage of an ABC dry chemical over a carbon dioxide extinguisher is（）. ["lack of toxicity","the multipurpose extinguishing ability","bum-back protection","cooling ability"]
半结构式访谈主要形式包括重点访谈和（）。 ["个人访谈","深度访谈","客观陈述法访谈","座谈会访谈"]
差压式流量计测得的差压△P是什么压差？流量与差压的关系是什么？
