Suppose that Biuret reagent turns purple when it is added to an unknown substance. What can you conclude about the substance?

Which of the following is true about fossils? a. the relative age of fossils cannot be determined from their position in sedimentary layers. b. fossils found in lower layers of sedimentary rock are as old as fossils found in upper layers of sedimentary rock. c. fossils found in upper layers of sedimentary rock are older than fossils found in lower layers of sedimentary rock. d. fossils found in lower layers of sedimentary rock are older than fossils found in upper layers of sedimentary rock.

Those who hope that land reform will end the problem of mass poverty and social inequality throughout middle and south america often cite as one of the causes of the problem. a. asian immigrants b. the indigenous population c. european systems of landholding d. the power of the roman catholic church

What mountain is the highest mountain in europe?