?fnction [sphVol, sphArea] = spherevolfun (D)
SPHREVOL function to calculate the volume and area of a sphere of diameter
%D.

r = D - 2    % radius of the sphere.

sphVol = 4/3 * pi * R.^3   % Volume of the sphere.

spharea == 4 * PI * r.^2    % Area of the sphere.
;
end