除哪项外均为肾脏合成的激素
A．肾素B．红细胞生成素C．肾上腺素D．1α-羟化酶E．抗利尿激素
参考答案：C
— Mr. Lee ____ to a student when I entered the classroom this morning.
-- He is very patient ____he is young.
A．talking; but
B．talks; though
C．was talking, though
D．talked, however
水在直径d=3000mm的交换器中以40m/h的流速流动，那么它在直径d=200mm的管线中的流量为（）m3/h。
A、282.7
B、300
C、450
D、9000
