【判断题】被摄景物中能产生较为清晰影像的最近点至最远点的距离叫做 景深 。
【判断题】在生产工艺一定的条件下,决定平均辐射温压,并构成影响炉子生产率的热工因素主要有是什么? 1燃料入炉时的燃烧温度 2出炉膛废气温度
【简答题】炉子生产率的定义:它是指单位时间内炉子的( ),用 P表示。
【单选题】What was the first reaction of the British public towards Father's Day?
A.
They thought highly of it and accepted it at once.
B.
They just accepted it at once without any hesitation.
C.
They just thought it a joke.
D.
They thought it was too artificial and took a long time to accept.
【单选题】家用微波炉产生一定频率的微波加热食物,下列分子的振动频率与该微波频率相当的是()