单项选择题
The responsibilities of a food and drug administration bureau is().
A.to set up rules about the use of pesticides and enforces them all over the country.B.to make sure any hole that might allow pests to enter a building should be filled.C.to check that doors and windows are completely closed.
单项选择题 Why is it necessary for supervisors to make a list of pest control measures?()
单项选择题 Outer walls are built().
单项选择题 From the text,we know that like chlorine,iodine or bromine are all().