货车辗钢整体车轮（D、Dl、E型）轮辋厚度的运用限度为（）mm。
参考答案：23
There were no women in the committee 1976, but now women are in a majority.
A．before to
B．previous to
C．ago
D．earlier
为什么具有弱酸性基团或弱碱性基团的盐性离子交换树脂，易于水解？
