带ABS的制动系，可采用哪种规格的制动液（ ）。 A: DOT　1 B: DOT　2 C: DOT　3 D: DOT 4

If F is a vector field, then divF is a vector field.

In the vector field, the vector line is such a curve where ( ) A: The tangent direction at each point on it is orthogonal to the direction of the vector field at that point. B: The tangent direction at each point on it is parallel to the direction of the vector field at that point. C: The value of each point on it is equal to the value of the vector field at that point. D: The vector line is the geometric curve of the vector field function.

下列创建vector容器对象的方法中,错误的是( ) A: vector v(10); B: vector v(10, 1); C: vector v{10, 1}; D: vector v = (10, 1);

The coordinates of a vector relative to a basis in a vector space is unique.

下面哪条语句创建了一个存有10个整数的vector对象？ A: std::vector<int> v(10); B: std::vector v; C: std::vector v[10]; D: std::vector<int> v[10]; E: std::vector(int) v;

Any subset of a vector space V which contains the zero vector is a subspace of V.

关于相对导数与绝对导数的关系，正确的是_____。 A: $\dot r = \tilde{\dot r}$ B: $\left| {{\bf{\dot r}}} \right| = \left| {{\bf{\tilde{ \dot r}}}} \right|$ C: ${\bf{\dot r}} = {\bf{\tilde{ \dot r}}}$ D: 以上都不正确

载体（vector)

If a is known to be a 2×3 matrix, then after executing a=a(:), ( ). A: a transforms to a column vector B: a transforms to 3 rows and 2 columns C: a transforms to 3 rows and 3 columns D: a transforms to 2 rows 3 and columns