There ______ a bank in the neighborhood. [ ]
A. has
B. have
C. is
D. are
答案：C
截面为矩形的折弯件其展开长度按什么计算？
Kij称为电极的选择性系数，通常Kij≤1，Kij值越小，表明电极的选择性越高。( )
