【单选题】What is the main idea of the passage?
A.
The analysis on the positive and negative side of innovation.
B.
The optimistic aspects of the development of innovation.
C.
The pessimistic prediction of the development of innovation.
D.
The main problem facing innovation and the solution.
【单选题】In the flat triangular surface depicted above, if feet, what is the area of the surface in square feet? (Figure not necessarily drawn to scale.)
【判断题】校正连杆弯扭变形时,应先校正弯曲变形,再校正扭曲变形。
【判断题】妊娠过程中需要维持高浓度的孕激素。( )