Which of these is the BEST indication of the relative age of a rock layer? the position of the layer compared to other layers o the distance the layer extends over the Earth o the chemical make-up of the layer O the thickness of the layer

Which of the following is not a defining characteristic of plants?

African penguins, which inhabit the coasts of southern africa, were classified as an endangered species in 2010. two significant threats to their survival are ecosystem damage from oil spills and overfishing by humans. overfishing depletes the food supply of african penguins. the best method to reduce the threat of overfishing would be to . the risk of oil spills could be reduced by increasing the use of , which should oil consumption. if an oil spill does occur, could be used to remove the oil so the ecosystem may more quickly recover.

Which of the following is the earliest era of earth's geologic time scale? cenozoic mesozoic precambrian paleozoic