Lenght of graph depends on what?

I have some basic level problems.

I want to extend my plot even further to see it more. i changed value of N and TIME but that didnot help

Can anyone kindly comment what does the lebght of graph exactly depends on? How can i make it run for more long so I can see where DA3 output touches X axis again....

T=10/wu;
N=100;
time=1:1:N;
time=T*time/N;
y1t=subs(y1tid,{t},{time});
y22t=subs(y2tid,{t},{time});
x1t=subs(x1t,{t},{time});
noise = 0.000001*rand (1,length(time));

y2t= y22t;
figure(nfig);
subplot(2,1,1);
plot(time*1e9,x1t,'-k','LineWidth',2);
hold on;
grid on;
xlabel('Time - [ns]');ylabel('Amplitude - [V]');
title('map Transient');
subplot(2,1,2);
plot(time*1e9,y1t,'--k','LineWidth',2);
hold on;
grid on;
plot(time*1e9,y2t,'-k','LineWidth',2);%y2t
xlabel('Time - [ns]');ylabel('Amplitude - [V]');
hold on;
grid on;

function [da1]=DA1_T(tf,tf2,tf3,ip)
global nfig  T time;
syms t;

%%%%%%%%%%%%%%%%%%%%%%%%%Time Domain DA1-DA3 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%%%%%%%%Time Domain DA1 %%%%%%%%%%%
da1=ip*tf;
da11=ilaplace(da1);
da1t=subs(da11,{t},{time});

%%%%%%%%%%%Time Domain DA2 %%%%%%%%%%%
da2=da1*tf2;
da2s=ilaplace(da2);
da2t=subs(da2s,{t},{time});

%%%%%%%%%%%Time Domain DA3 %%%%%%%%%%%
da3=da2*tf3;
da3s=ilaplace(da3);
da3t=subs(da3s,{t},{time});


close all
figure;

%subplot(4,1,1);  
plot(time*1e9,da1t ,'-b','LineWidth',2);
xlabel('Time - [ns]');ylabel('Amplitude - [V]');
title('DA1 time Output ');
hold on
grid on
  
%subplot(4,1,2); 
plot(time*1e9,da2t ,'-r','LineWidth',2);
xlabel('Time - [ns]');ylabel('Amplitude - [V]');
title('DA2 time Output ');
hold on
grid on
%subplot(4,1,3); 
plot(time*1e9,da3t ,'-k','LineWidth',2);
xlabel('Time - [ns]');ylabel('Amplitude - [V]');
title('DA Transient Output ');
hold on
grid on
axis([0 100 -0.5 inf])
legend('DA1','DA2','DA3');

[Rena Berman]

(Answers Dev) Restored edit