Define - Astronomical unit?

Define a Astronomical Unit.

How many parallactic second are there inone Astronomical unit? 1 parallactic second =3.08xx10^(16)m 1 Astronomical unit =1.496xx10^(11)m

One Astronomical unit is.........

How many Astronomical units are there in one light year? Given Data: 1 Astronomical unit =1.496xx10^(11)m 1 light year =9.46xx10^(15)m

Which of the following is not the unit of time? a) Light year b) Astronomical unit c) Parsec d) all of the above

One astronomical unit is equal to ________.

The orbit of Halley's comet is an ellipse 36.18 astronomical units long and 9.12 astronomical units wide. Find its eccentricity.