特种设备事故造成10人以上30人以下死亡，或者50人以上100人以下重伤，或者5000万元以上1亿元以下直接经济损失的，为重大事故。
参考答案：对
Which statement about the risks of bond investing is FALSE（）
A. Issuers of revenue bonds are not always obligated to pay principal and interest.
B. Interest on some municipal bonds is not excluded from federal income taxes.
C. In a competitive Treasury-bill auction, not all bidders pay the same price.
论述我国土壤水平地带性分布规律
