对商品混凝土早期强度提高作用最大的外加剂为（）。

单项选择题钻铤的主要特点是（）。

A.壁厚大、重量大
B.壁厚大、刚度大
C.壁厚大、重量大、刚度大

单项选择题Which of the following could be an appropriate title for this passage?（）

A.Louis XIV and the Palace of Versailles.
B.The ceilings of the Hall of Mirrors.
C.The Amazing Palace of Versailles.
D.A History of France.

单项选择题Which of the following is not mentioned as a feature of the Hall of Mirrors？（）

A.Bronze moldings.
B.Ornate paintings.
C.Marble fixtures.
D.Crystal chandeliers.

单项选择题about this articles which of the following is NOT true？（）

A.The Hall of Mirrors has been recently restored.
B.The Hall of Mirrors is considered the centerpiece of the Palace of Versailles.
C.The Hall of Mirrors features a parquet floor.
D.Two major treaties were signed in the Hall of Mirrors.

单项选择题Why did King Louis XIV want a grand palace？（）

A.So he and his queen could retire comfortably.
B.As a hunting chateau.
C.As a place to conduct his nation's business.
D.He wanted to impress his wife.