【单选题】_____ people know _____ about it. [ ]
【单选题】If someone sends a message the size of one gigabyte, ______.
C.
it takes little time for a computer to read
D.
it is the size of a short note
【单选题】斜率为2的直线经过点A(3,5)、B(a,7)、C(-1,b)三点,则a、b的值为( )
【单选题】对于变桨变速型风力发电机组,通过调节( )以确保机组在额定风速以上时可以维持额定功率的输出,并且确保机组可以安全停机。