In an experiment to determine the effects of radiation on the germination of seeds, a factor that has to be controlled is a. the amount of radiation. b. the types of radiation. c. the germination rate of seeds. d. the amount of water added to the seeds.

How many major plates cover the earth

Someone me with this: a mineral' is determined by its actomic structure.

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.