433.8 light years
Polaris is about 430 light-years away from Earth, or 4.07 * 1018 meters, or 2.53 * 1015 miles.
4,096,409,000,000,000,000 metres (4.096409 x 1018 metres) or 433 light years.
Exactly 630-680 nano-meters. If you wanted it in another unit you should have asked that.
680 miles
They lived over 5,000 years ago.
The current north star, known as Polaris, has a distance estimated at 325-425 light-years. From Wikipedia: "Many recent papers calculate the distance to Polaris at about 434 light-years ... Some suggest it may be 30% closer ..."
Rhubarb was cultivated in the Far East over 2000 years ago
The outlaw 525 by far
Polaris, also known as the North Star, is about 434 light years, or about 4.1 quadrillion kilometers, from earth.
Distances to stars are not measured in kilometres, but since you have asked, Polaris is 3-4 quadrillion kilometres away.
Neither, as far as we know. Current scientific evidence points to a beginning around 4.6 billion years ago.