GAAS80/700钢轨闪光焊的“I”记录曲线上电流值异常说明DX300（）装置出现故障。
参考答案：可控硅触发
After several sleepless nights, Mr. Smith ______ a perfect solution to the problems.
A．kept up with
B．put up with
C．came up with
D．ended up with
发展中国家有哪些基本特征？
