第2部分:阅读判断(第16~22题,第题1分,共7分)
6 w5 R) q1 v: d' ? 下面的短文后列出了7个句子,请根据短文的内容对每个句子做出判断:如果该句提供的是正确信息,请选择A;如果该句提供的是错误信息,请选择B;如果该句的信息文中没有提及,请选择C.
5 O# d7 P; A, n6 @; h, e% u3 `$ kBlack Holes
5 {, v& ]+ i" O: M Most scientists agree that black holes exist but are nearly impossible to locate.A black hole in the universe is not a solid object,like a planet,but it is shaped like a sphere (球体).Astronomers(天文学家)think that at the center of a black hole there is a single point in space with infinite(无限的)density(稠密).This single point is called a singularity (奇点).If the singularity theory is correct,it means that when a massive star collapses,all the material in it disappears into the singularity.The center of a black hole would not really be a hole at all,but an infinitely dense point.Anything that crosses the black hole is pulled in by its great gravity.3 C l0 P$ o/ k0 t2 y+ f
Although black holes do exist,they are difficult to observe.These are the reasons.
i3 M" J8 @7 j# z& v ● No light or anything else comes out of black holes.As a result,they are invisible to a telescope.
1 p& l ]) R* B ● In astronomical terms,black holes are truly.For example,a black hole formed by the collapse of a giant star would have an event horizon(视界)only 18 miles across.9 }- b; }% b# A* K9 ?) E2 L; X
● The nearest black holes would be dozens of light years away from Earth.One light year is about 6 trillion(万亿)miles.Even the most powerful telescopes could not pick out an object so small at such a great distance.
9 ?* W% |# B6 G* A' E. a R5 y In 1994 the Hubble Space Telescope provided evidence that black holes exist.There are still answers to be found,however,so black holes remain one of the mysteries of the universe.
# D- {% z$ F; G- `: g" I 16.Black holes are part of space.
. x; |, E* v D3 v A.Right B.Wrong C.Not mentioned* n" |1 p& w6 |4 W; Q! W+ x
17.Black holes exist but are difficult to observe.
7 m9 X5 i+ x- F5 S0 W6 p6 M2 O8 \ A.Right B.Wrong C.Not mentioned
4 c5 D0 @9 {' F+ y 18.The center of a black hole is empty./ {/ P; n# q% z/ ]
A.Right B.Wrong C.Not mentioned
# x' g+ p: V1 t) c 19.The attraction of two large stars leads to gravity.( U0 d! [ d% e/ d- {
A.Right B.Wrong C.Not mentioned. q5 z$ L0 ^$ d
20.The sun is the heaviest star in the universe.! z; o: S! [2 M; m9 t; r
A.Right B.Wrong C.Not mentioned; d: m( G; f8 u! p* m4 ~
21.The nearest black holes are hundreds of light years away from us.7 j* j M' B! |+ w+ `& V
A.Right B.Wrong C.Not mentioned
0 J' ?; X, C D& f G2 w 22.The Hubble Space Telescope helps scientists to understand the nature of the universe.) ]5 ^ C0 n2 P e1 R/ F6 |! p$ s; X
A.Right B.Wrong C.Not mentioned |