What were the gases Miller and Urey used to recreate the early
atmosphere? Choose all that apply.
methane
oxygen
hydrogen
e
ammonia

Is becoming less expensive to screen blood samples for dna certain diseases have genetic basis what is possible ethical concern about the availability of inexpensive dna testing

18. over time, how do sand dunes tend to migrate? a. perpendicular to the movement of the wind b. in the same direction as the wind blows c. toward the wind d. in random directions

The many stone tools, fragmentary animal bones, and teeth found at gran dolina, spain, indicate that hominids there? a. processed and consumed animals and other hominids. b. did not differ appreciably from earlier asian homo erectus. c. were similar to later homo sapiens. d. none of the above