which word refers to the part of a nuclear reactor in which the nuclear reaction takes place?
A.Vessel
B.Core
C.Circulation system
D.Control rods

What is the most likely reason why many Americans are still afraid of nuclear island?
A.They have heard about many accidents like the one at Three Mile Island.
B.They were at Three Mile Island
C.They believe that a situation like Three Mile Island could happen again
D.Nuclear power plants are always dangerous.

Which is the best place for the following sentence?“ Even so, this disaster stayed in the minds of many Americans.”
A.[1]
B.[2]
C.[3]
D.[4]

What is the topic of the passage?
A.Types of stars and how to observe them.
B.The differences between binary and variable stars
C.Types of telescopes
D.The color and temperature of stars

Which of the following is true of variable stars?
A.They vary in brightness
B.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 astronomer
B.To encourage people to try observing stars
C.To show that most people know a lot about stars
D.To explain why astronomy is popular

The word “parameters” in paragraph 1 is closest in meaning to
A.Measurements
B.Laws
C.Categories
D.Numbers

The word “ rudimentary” in paragraph 4 is closest in meaning to
A.Advanced
B.Formal
C.Basic
D.Important

Lewis and Clack had been gone for such long on their expedition that many thought they were dead.
A.Been gone
B.Such
C.Many
D.Were dead

Though it is one of the rarest metals, gold was one of the first to be discover.
A.Though
B.Rarest metals
C.The first
D.Discover