单项选择题
A. Women try to maintain their beauty by dressing up. B. Women like to show off their beauty. C. Women are born to be beauties. D. Women are proud of their beauty.
A. it can measure the movement of a spaceship less accurately than a microwave radar B. it is a new system of radar C. it provides precise measures of the velocity of space vehicles D. it is one thousand times more precise than microwave radar
A. laser-doppler radar is more accurate than microwave radar B. microwave radar operates at a higher frequency than laser-doppler radar C. the light-beam radar can measure only slow speeds with accuracy D. microwave radar may not ensure absolute precision in measuring varying speeds