台地上的典型层序是向上变浅的,即由()组成沉积层序。
A.潮上带一潮间带一潮下带
B.潮下带一朝上带一潮间带
C.潮下带一潮间带一朝上带
D.朝上带一潮下带一潮间带
参考答案:C
民族精神既是过去的,也是现在的,又指向未来。这主要表明 ( )
A.文化创新的重要性
B.继承优秀文化传统的重要性
C.文化交流与传播的重要性
D.民族精神的形成和发展是长期历史积淀的过程
A pyramidal-shaped box to protect a plant is constructed with 4 lateral faces and an open bottom. What is the lateral area of the box ?() (1)The base of the pyramid is a polygon with all sides of equal length, and the perimeter of the base is 1 meter. (2)The 1ateral faces are isosceles triangles that have the same size and shape.
A.条件(1)充分,但条件(2)不充分.
B.条件(2)充分,但条件(1)不充分.
C.条件(1)和(2)单独都不充分,但条件(1)和条件(2)联合起来充分.
D.条件(1)充分,条件(2)也充分.
E.条件(1)和条件(2)单独都不充分,条件(1)和条件(2)联合起来也不充分.