According to the characteristics of the capital market, which of the following is most directly a function of primary capital markets and which is most directly a function of secondary capital markets Primary capital marketsSecondary Capital markets（）①A. Source of liquidity Security underwriting ②B. Source of new capital Source of price information ③C. Source of price information Source of new capital

A. ①

B. ②

C. ③

下列关于风荷载的表述中，正确的是( )。

A．风荷载仅对结构产生压力

B．风荷载值的大小与建筑物形体有关

C．风荷载属于偶然荷载

D．风荷载值的大小与风速无关