(1)\ area:\hspace{85} S=ab\pi,\hspace{20} b\le a\\
(2)\ circumference:\\
\hspace{20} L=4aE(k),\hspace{20} k=\sqrt{1-({\large\frac{b}{a}})^2}\\\vspace{5}
\hspace{20} E(k):\ 2nd\ complete\ elliptic\ integral\\(3)\ ellipticity:\hspace{40} c={\large\frac{b}{a}}\\\vspace{5}
(4)\ linear\ eccentricity :\ f=\sqrt{a^2-b^2}\\">