【B11】A.throughB.toC.atD.in
【B11】
A.through
B.to
C.at
D.in
【B11】
A.through
B.to
C.at
D.in
A.the satisfaction of certain physiological needs
B.their strong desire to solve complex problems
C.a basic human desire to understand and control the world
D.a fundamental human urge to display their learned skills
The model has shown that this radar system, known as laser-dopple radar, can measure with absolute precision speeds varying from spaceship orbital injection(进入) velocities(速度) of five miles per second down to virtual stops-speeds of less than one-thousandth of an inch per second. According to the scientists who are developing this system, such fine measures of velocity are of prime importance in space missions. In a rendezvous(对接) between two spaceships, or in a landing approach by a vehicle onto an orbiting space station, a bump could rip open a ship's skin, or a nudge could knock the station out of its orbit.
The light-beam radar, which operates at a frequency of trillions of cycles(百万兆) per second, could easily detect and measure the movement of a vehicle edging up to a satellite space station. A control system using so precise a signal as this would allow a huge vehicle to dock at a space station as lightly as a feather.
Laser-dopple radar ______.
A.measures the movement of a spaceship by means of light beam
B.makes use of microwaves
C.makes use of sound waves
D.both A and B
听下面5段对话。每段对话后有一道小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。每段对话仅读一遍。
听力原文:W: What is the deadline for the term paper,sir?
M: Since it should be about 10 type-written pages long,you can hand it in next week.
What is the probable relationship between the two speakers?
A.Manager and clerk.
B.Director and secretary.
C.Professor and student.
A.we have either
B.so have we nothing
C.neither have we
D.nor have we noting
A.understand
B.understood
C.understand by
D.understood by
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