Which of the following is true of variable stars?A.They vary in brightnessB.They rotate around each other.C.They vary in color.D.The size of the telescope must vary in order to observe them.
Why does the author write that “stellar astronomy is possible for everyone”?A.To emphasize that it is easy to become an astronomerB.To encourage people to try observing starsC.To show that most people know a lot about starsD.To explain why astronomy is popular
The word “parameters” in paragraph 1 is closest in meaning toA.MeasurementsB.LawsC.CategoriesD.Numbers
The word “ rudimentary” in paragraph 4 is closest in meaning toA.AdvancedB.FormalC.BasicD.Important
Lewis and Clack had been gone for such long on their expedition that many thought they were dead.A.Been goneB.SuchC.ManyD.Were dead
Though it is one of the rarest metals, gold was one of the first to be discover.A.ThoughB.Rarest metalsC.The firstD.Discover
_________(36)A.announcementsB.positionsC.decisionsD.locations
_________(38)A.betterB.openC.difficultD.worsening
_________(39)A.motionB.useC.saleD.method
_________(41)A.byB.inC.backwardsD.from
Loga.vn - Cộng Đồng Luyện Thi Trực Tuyến