Try to explain your choice grammatically.

Read the text and explain what the difference is between the Scalar and Vector Quantities.

Scalar and Vector Quantities

Scalar Quantity. — There are many quantities, such as mass, time, area, volume, etc., that have only magnitude. They do not involve any idea of direction and are completely known when their magnitudes are specified. Such quantities obey the ordinary laws of addition, subtraction, multiplication, and division. A field has an area of 10 acres. To it is added another field containing 3 acres. The combined fields now have an area of 13 acres. A block of wood weighs 8 lb. A piece weighing 3 lb. is cut off. The remainder weighs 5 lb. These are illustrations of the addition and subtraction of scalar quantities. A Scalar quantity is a quantity that has magnitude only.

Vector Quantity. — Quantities such as force, weight, displacement
and velocity which have both magnitude and direction are known as
vector quantities. They require knowledge of both magnitude and direction for their complete description. They cannot be added, subtracted,
multiplied, or divided according to the ordinary methods of arithmetic, but must be added, subtracted, multiplied, or divided vectorially. For example, a force of 8 lb. directed east and a force of 6 lb. directed north are equal to a force of 10 lb. in a direction north of east. A vector quantity is a quantity that
has both magnitude and direction.

A vector quantity can be represented by means of a straight line. The length of the line represents the magnitude of the vector. The direction of the line represents the direction of the vector, and an arrowhead on the line shows the sense in which the vector is to be taken. A line 2 in. long pointing directly east may represent a force of 20 lb. acting toward the east.

If a body moves from one position to another, it is said to have had a displacement. For example, a body is moved from position A to position В and then from В to C. It has experienced two displacements, and these two displacements are equivalent to a single displacement from A to C, In each case the length of the line represents the magnitude of the displacement, the direction of the line represents the direction of the displacement, and the arrowhead on the line shows the sense in which the displacement took place. Since displacements have both magnitude and direction, they are vector quantities [2, С. 44 - 45].

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