汽轮机冷态启动，当凝结放热结束时，蒸汽开始以（）向金属传递热量。
参考答案：对流放热
无风险收益率是指可以确定可知的无风险资产的收益率，与通货膨胀无关。 ( )
Yesterday I met him at the street, but we hadn't planned to meet. We meet ____ chance. [ ]
A. of
B. in
C. for
D. by
