Oral route. Many drugs can be administered orally as liquids, capsules, tablets, or chewable tablets. Because the oral route is the most convenient and usually the safest and least expensive, it is the one most often used. However, it has limitations because of the way a drug typically moves through the digestive tract.
Measuring Distances to Stars. Astronomers use several techniques for discovering how far away an object is. The first is called trigonometric parallax and is based on geometry, but it is only good for up to about 500 light-years.
The star is 25,000 light-years away from Earth. Despite this great distance, the star would be visible to the naked eye if it were not for all the dust between it and the Earth. UPDATE! As of January 2009, we now know about some other really big stars. One is called Eta Carinae.