Look at the representation of a hillside below. the symbols in each stratus of the cross-section represent fossils of different organisms. which of the following organisms must have evolved first? % * ^ ^ * % $ $ $ # # # * * * * * $ * * * $ $ # # # # @ % # # # @ @ ! ! ! ! * * @ < < < < < + + + + = = a* b# c@ d$

Which statement about the immune system is false? a. lymphocytes reduce inflammation, b. b cells remember specific pathogens. c. most white blood cells kill bacteria d. white blood cells are made in lymph nodes.

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.

When rutherford performed his metal foil experiment, he was surprised that most of the alpha particles