Can anyone explain this graph?

This exercise is for Mass-Spring System Model I need someone put comments about the obtained result .........title pf the graph is not enough

**Create a MATLAB-function and save it by the name mass_spring.m

% Firstly, this M-file to define the function of the position to time function dXdt = mass_spring(t, X)

% Enter the values of the given parameters,

M=750; % (Kg)

B=30; % ( Nsec/m)

F=300; % N

K=15; % (N/m) dXdt(1) = X(2);

dXdt(2) = -B/M*X(2) - K/M*X(1) + F/M;

dXdt = [dXdt(1) dXdt(2)]';

****Now, create an M-file and name it as Excr3.m, as following

X0=[0 ; 0]; % (initial speed and position)

[t,X] = ode45('mass_spring', [0 200] , X0);

plot(t, X(:,1),'o-', t, X(:,2),'*-');

title('Mass-Spring Model time response to a constant traction force F(t) ') grid

After entering the code I got this Graph I need someone explain form me this graph

Note the acceleration is: a=(dv(t))/dt=(d^2 x(t))/(dt^2 )

Velocity (speed) is v=(dx(t))/dt

and, displacement is x(t)

[David Sanchez]

We all need many thinks: peace, love....

But it does not mean we have to forget the basics of politenes.

What about asking thinks properly with its pleases and thanks?

To understand the plot, just read the title.

[Mohammad]

I need comments about the obtained result title is not enough