周初先后分封了71个诸侯国,其中周武王姬发封其兄弟立国者15人,姬姓立国者40人。这说明分封制的突出特点是[ ]
A.等级
B.血缘
C.嫡长子继承
D.世袭
答案:B
A、B、C三种固体物质的溶解度随温度变化的曲线如图所示,请回答下列问题:
(1)在50℃时,A物质的溶解度是______g.
(2)在40℃时,A、B、C三种物质的溶解度由大到小的顺序是______.
The tools and techniques of quantitative risk analysis are______.
A.contracting,contingency planning,alternative strategies,and insurance
B.interviewing,historical results,workarounds,and additional response development
C.checklists,damage control reports,standard allowances, and inspection
D.data gathering and representation techniques,and quantitative risk analysis and modeling techniques