Answer;
-Mass
Explanation;
-An intensive property is a physical quantity whose value does not depend on the amount of the substance for which it is measured. For example, boiling point, density, color, melting point, Odor, temperature, etc.
-Extensive properties on the other hand, do depend on the amount of matter that is present. An extensive property is considered additive for subsystems. Examples of extensive properties include: volume, mass, size, weight. length, etc.
To solve this problem we will use the Ampere-Maxwell law, which describes the magnetic fields that result from a transmitter wire or loop in electromagnetic surveys. According to Ampere-Maxwell law:

Where,
B= Magnetic Field
l = length
= Vacuum permeability
= Vacuum permittivity
Since the change in length (dl) by which the magnetic field moves is equivalent to the perimeter of the circumference and that the electric flow is the rate of change of the electric field by the area, we have to

Recall that the speed of light is equivalent to

Then replacing,


Our values are given as




Replacing we have,



Therefore the magnetic field around this circular area is 
If you dropped a ball from any height, and measured its distance from the ground at any regular interval while it's falling, the graph of that distance versus time would be a graph that curves downward.
-- The ball is falling down. As time goes on, it gets closer and closer to the ground. Its remaining distance from the ground keeps decreasing, so the line on the graph slopes down.
-- The speed of the ball keeps increasing (it accelerates) because of the gravitational force on it. As time goes on, it covers more of the remaining distance during each interval than it did in the previous interval. The downward slope of the graph keeps increasing.
Https://www.researchgate.net/publication/335238337_A_New_Strategy_for_Improving_the_Tracking_Performance_of_Magnetic_Levitation_System_in_Maglev_Train/fulltext/5d5a958d299bf1b97cf546ba/A-New-Strategy-for-Improving-the-Tracking-Performance-of-Magnetic-Levitation-System-in-Maglev-Train.pdf?origin=publication_detail
The higher the phase margin the more stable is the system and for these tuned parameters, the phase margin is around
. Some researcher given their theory on the phase margin that there are changes of getting sluggish response for larger phase margin but using TLBO algorithm the settling time and as well as peak overshoot of the system shows better response as compared to conventional techniques.