Wich of the folling is best definition of vectors (quantities described by both force and gravity)(quantities described by bothspeed amnd movement)(quantities described by both velocity and acceleration)(quantities described by both magnitud)

Option D is quantities described by both magnitude and direction is the correct answer.

Explanation:

A scalar is quantity with magnitude only. It does not have direction. Examples of scalar are distance, speed, time etc.

A vector is quantity with both magnitude and direction. Some examples for vectors are displacement, velocity, acceleration, force, moment, electric field, magnetic field etc.

Here option A, quantities described by both force and gravity is not correct.

Option B is quantities described by both speed and movement is also not correct.

Option C is quantities described by both velocity and acceleration is also not correct.

Option D is quantities described by both magnitude and direction is the correct answer.

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.