function vap_plotter(Tvap, A, Tvap_air)
global Tk
n = length(Tvap);
T1 = Tvap-Tk;
T2 = Tvap_air*ones(n+1, 1)-Tk;
for i = 1:n
  z(i) = sum(A(1:i))/sum(A);
end
z = [0; z'];
T1 = [T1(1); T1];
figure
plot(z, T1, z, T2)
title('Evaporator')
legend('T1', 'T2')
