单项选择题
An example of a grade B product is（）.
A.piperyline B.motor gasoline C.kerosene D.mineral spirits
单项选择题 An entry of water，gas，oil，or other formation fluid into the wellbore is called a（）.
单项选择题 An engine compartment gasoline fire requires which type of extinguisher?（）
单项选择题 An azimuth angle for a body is measured from the（）.
