Countour function And meshgrid

How do you part B and this is what I have for both A and B and I've attached the question and what is supposed to look like.

    % code 
% Code for part A
% Given Values
C = 15E-6;
Vm = 24; 
L = 240E-3;
R = [10:1:40];
f = linspace(60,110,31); 
[f2, R2] = meshgrid(f, R);
w = 2*pi*f;
w2 = 2*pi*f2;
% Compute function surface.
Top = Vm;
Bottom = sqrt(R2.^2 + (w2*L-(1./(w2.*C))).^2); 
I = (Top./Bottom)';
% Now plotting everything.
mesh(R, w, I);
ylabel(' w (angular frequency)')
xlabel('R Ohms')
zlabel('I Amps')
view(gca,[-133.1 34.8]);
grid('on');

% Code for part B figure contour(w,R,I) xlabel('w (angular frequency)') ylabel('I (amps)')

end