How do you read the number “3,054,003”?

A．three million, and fifty-four thousands, three

B．three million, and fifty-four thousand and three.

C．three million, fifty-four thousand, three.

D．three million, fifty-four thousand and three.

造成离心泵的振动的原因有（）。

A、泵转子不平衡

B、机组找正不合要求

C、轴弯曲

D、泵进口堵塞