Betelgeuse is one of the brightest stars in the night sky even though it is 640 LY from Earth. Barnard's Star, on the other hand, is relatively close but is not visible to the unaided eye.
Which of the following is a correct explanation for this?

Which of these is a drawback of using natural gas? a. it is fairly safe for use in homes.b. it burns more cleanly than crude oil products.c. scientists have developed new ways of extracting it.d. during its extraction, groundwater can be contaminated.