Darwin focused on studying specific species on the galapagos islands and other places and observed

the genetic makeup of the individual species
that fossils tell us about the past
similar species in different areas with unique traits
how individuals grow in numbers

the correct answer would be 6 feet.

oak trees? ? what was listed

blue stars have the highest surface temp

stellar distances are usually expressed in light-years

the measure of a star's brightness is called magnitude

hope this !

there's the proffessional site that will you.