单项选择题
Deneb is found in what constellation?（）
A.Cygnus B.Pegasus C.Ursa Major D.Andromeda
单项选择题 Define the acronym MSI（）.
单项选择题 Deficient oxygen content inside a chain locker can be detected with（）.
单项选择题 Deck beams on a ship are generally spaced at equal intervals and run（）.
