A.10天 B.30天 C.40天 D.60天
A.1個(gè)月 B.2個(gè)月 C.1周 D.3周
A.總蟲(chóng)數(shù)/陽(yáng)性房間數(shù) B.總蟲(chóng)數(shù)/陽(yáng)性房間數(shù)×100% C.總蟲(chóng)數(shù)/查房間總數(shù) D.總蟲(chóng)數(shù)/查房間總數(shù)×100%