Oh my God...such a tricky question...

Suppose there is a planet revolving about a star of mass ' M kg ' in an elliptical path of eccentricity ' e '. The mass of the planet is ' m kg ' and its time period is ' T '. The speed of the planet at any instantaneous position 'A' (on the ellipse) is ' 100 m/s ' ..Find the speed of the planet at position 'B' which is diametrically opposite to position 'A' .( in m/s)?

DETAILS and ASSUMPTIONS :--

1) the system follow all Newton and Kepler laws

2) The position of star is always fixed

3)'M'= " 7.154 x 10^(14) (10 to the power 17) kg.. 'e'= 0.7071.

4)'m'=2000 kg..Time period 'T'= 5 minutes (300 seconds)