To calculate the free surface correction，it is necessary to divide the free-surface moments by the（）.

The effects of free surface on initial stability depend upon the dimensions of the surface of the free liquids and the（）.

As the displacement of a vessel increases，the detrimental effect of free surface（）.

The effects of free surface on a vessel’s initial stability do NOT depend upon the（）.

On the surface of a perfect conductor, the normal component of the electric displacement vector is A: continuous with the normal component of the electric displacement vector inside the conductor B: uncertain C: equal to the surface density of free charge on the conductor surface. D: equal to zero

______ is covered with heavy snow. A: The surface of earth B: The earth’s surface C: The earths’ surface D: The surface

_____ is covered with heavy snow. A: The earth’s surface B: The surface of earth C: The surface earth D: The earth surface

What is the name of the solid surface in the figure below?[img=360x664]1803bb9e6fc6d99.jpg[/img] A: circular cone surface B: Cone-shaped surface C: Cylindrical surface D: Columnar surface

For soft tooth surface gear transmission, the hardness of the tooth surface should be selected A: Pinion tooth surface hardnesslarge gear tooth surface hardness B: Pinion tooth surface hardness≤large gear tooth surface hardness

The principles for machining sequence of each surface should be( )<br/>and perform rough machining before finish machining. A: perform datum surface machining before that of other surfaces B: perform main functional surface machining before less important surface machining C: perform plane surface machining before hole surface machining D: perform complex surface machining before simple surface machining