UPS电池（12V）浮充时全组各电池端电压的最大差值不大于（）。
A.240mv
B.90mv
C.120mV
D.480mv
参考答案：D
Entering the room, I found Mary ______at the desk and _____a letter.
A．seated; wrote
B．sitting, written
C．seating; writing
D．seated; writing
何谓过期妊娠？其胎儿有哪些生长模式？
