What is a unit vector? A) a vector with all three directions or
dimensions (x, y and z or i, j, k) that are given
B) a vector with only one dimension
C) a vector that has an x and y components that
D) are equal in magnitude
a vector with a magnitude of one

A unit vector is (D) a vector with a magnitude of one

Explanation:

Unit Vector Information:

A unit vector is a vector with a magnitude of one. Vectors of different magnitudes can be scaled off the unit vector. Also, they can be used in two, three, or more dimensions.

Other Answers:

A. a vector with all three directions or  dimensions that are given

This is the definition of a 3D vector. This is a line segment in three-dimensional space running from point A (tail) to point B (head). Each vector has a magnitude (or length) and direction.

B. a vector with only one dimension

This is the definition of an one-dimensional vector. This type of vector has no dimension, but a number of components, therefore it behaves like a real number.

C. a vector that has an x and y components that  are equal in magnitude

(Unsure, I believe this would be defined as an equal vector. Correct me if I'm wrong and I will edit it.)

I hope this helps!

a high pressure system is a dense air mass that is usually cooler and drier than the surrounding air. a low pressure system is a less dense air mass that is usually wetter and warmer than the surrounding air.

in general, areas that experience high atmospheric pressure also experience fair weather. low pressure systems can cause the formation of clouds and storms. air usually flows from areas of high pressure to areas of low pressure..

the answer is a. hope this .