I got ten out of ten on quiz #3.
Sometimes I'm lucky.

BTW, with Sol subjected to a cyclical radial velocity of about (+ -)12 meters/second
by Jupiter's gravity, the sine wave pattern generated over a 12 year orbital period
is NOT PERFECTLY symetrical...Because of the gravitational 'tug' of such planets
as Saturn, Uranus, Neptune...and, yes, Earth and Mars as well.

It would be interesting to examine the long-term [radial velocity] sine wave patterns of some of the stellar "primaries", with known jovian-mass exoplanets, to see if the sine wave patterns generated are being deformed and shifted by Earth-mass planets affecting the orbits of their jovian mass "secondaries".